Reintroduce nautobot.setup() function

[glennmatthews]

Closes #5531

What's Changed

In #5310 I removed the nautobot.setup() function as part of refactoring, not realizing that there were outside use cases relying on it. This resulted in:

• App Pylint Broken with 2.2.0 #5531 (pylint --init-hook "import nautobot; nautobot.setup()" ...)
• Nautobot 2.2.0 Default User Setup Fails nautobot-lab#93 (custom python script doing nautobot.setup() to be able to run Nautobot/Django code to create a default user)

This PR reintroduces a form of this function that works similarly but keeps the startup-sequence refactoring from #5310 in place otherwise.

As a bonus, we can adopt the same pattern used in Apps to run pylint, i.e. pylint --init-hook "import nautobot; nautobot.setup()" ... and therefore no longer have a need for the hackish nautobot-server pylint command that we'd added to the example_app as a workaround.

Screenshots

❯ invoke pylint                                                     
Running docker compose command "ps --services --filter status=running"
Running docker compose command "run --rm --entrypoint 'pylint --verbose --init-hook "import nautobot; nautobot.setup()" 
nautobot tasks.py' nautobot"
PYTHON_VER=3.8 \
docker compose \
    --project-name "nautobot" \
    --project-directory "/Users/glennmatthews/Documents/git-stuff/nautobot/development/" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.yml" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.postgres.yml" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.dev.yml" run \
    --rm \
    --entrypoint 'pylint \
    --verbose \
    --init-hook "import nautobot; nautobot.setup()"  nautobot tasks.py' nautobot
[+] Running 3/0
 ⠿ Container nautobot-db-1        Running                                                                          0.0s
 ⠿ Container nautobot-redis-1     Running                                                                          0.0s
 ⠿ Container nautobot-selenium-1  Running                                                                          0.0s
18:14:35.178 DEBUG   nautobot.core.celery __init__.py        import_jobs_as_celery_tasks() :
  Importing system Jobs
18:14:35.184 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.ExportObjectList
18:14:35.192 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositorySync
18:14:35.192 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositoryDryRun
18:14:35.192 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.ImportObjects
18:14:36.877 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleDryRunJob
18:14:36.878 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleJob
18:14:36.878 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleHiddenJob
18:14:36.878 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleLoggingJob
18:14:36.879 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleFileInputOutputJob
18:14:36.879 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleJobHookReceiver
18:14:36.879 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleSimpleJobButtonReceiver
18:14:36.879 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleComplexJobButtonReceiver
Using config file /source/pyproject.toml

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Your code has been rated at 10.00/10

Running docker compose command "ps --services --filter status=running"
Running docker compose command "run --rm --entrypoint 'pylint --verbose --init-hook "import nautobot; nautobot.setup()" 
--recursive=y development/ examples/' nautobot"
PYTHON_VER=3.8 \
docker compose \
    --project-name "nautobot" \
    --project-directory "/Users/glennmatthews/Documents/git-stuff/nautobot/development/" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.yml" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.postgres.yml" \
    -f "/Users/glennmatthews/Documents/git-stuff/nautobot/development/docker-compose.dev.yml" run \
    --rm \
    --entrypoint 'pylint \
    --verbose \
    --init-hook "import nautobot; nautobot.setup()" \
    --recursive=y development/ examples/' nautobot
[+] Running 3/0
 ⠿ Container nautobot-selenium-1  Running                                                                          0.0s
 ⠿ Container nautobot-redis-1     Running                                                                          0.0s
 ⠿ Container nautobot-db-1        Running                                                                          0.0s
18:20:30.450 DEBUG   nautobot.core.celery __init__.py        import_jobs_as_celery_tasks() :
  Importing system Jobs
18:20:30.455 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.ExportObjectList
18:20:30.465 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositorySync
18:20:30.465 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositoryDryRun
18:20:30.465 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.ImportObjects
18:20:32.787 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleDryRunJob
18:20:32.788 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleJob
18:20:32.788 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleHiddenJob
18:20:32.788 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleLoggingJob
18:20:32.789 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleFileInputOutputJob
18:20:32.789 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleJobHookReceiver
18:20:32.789 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleSimpleJobButtonReceiver
18:20:32.790 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_app.jobs.ExampleComplexJobButtonReceiver
Using config file /source/pyproject.toml

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Your code has been rated at 10.00/10

TODO

• Explanation of Change(s)
• Added change log fragment(s) (for more information see the documentation)
• Attached Screenshots, Payload Example
• n/a Unit, Integration Tests
• n/a Documentation Updates (when adding/changing features)
• Example App Updates (when adding/changing features)
• Outline Remaining Work, Constraints from Design