Update README with how-to information

[michplunkett]

Describe your changes

Filled in the last bit of how-to information.

Non-obvious technical information

N/A

Checklist before requesting a review

• The code runs successfully.

(poetry-python-project-py3.11) michaelp@MacBook-Air-3 python_project_template % make lint
pylint project/ test/

------------------------------------
Your code has been rated at 10.00/10

(poetry-python-project-py3.11) michaelp@MacBook-Air-3 python_project_template % make format
black project/ test/
All done! ✨ 🍰 ✨
4 files left unchanged.
(poetry-python-project-py3.11) michaelp@MacBook-Air-3 python_project_template % make test
pytest -vs test/
=========================================================================== test session starts ===========================================================================
platform darwin -- Python 3.10.9, pytest-7.2.0, pluggy-1.0.0 -- /opt/homebrew/opt/python@3.10/bin/python3.10
cachedir: .pytest_cache
rootdir: /Users/michaelp/Documents/GitHub/python_project_template
collected 1 item                                                                                                                                                          

test/test_example.py::test_example PASSED

============================================================================ 1 passed in 0.00s ============================================================================
(poetry-python-project-py3.11) michaelp@MacBook-Air-3 python_project_template % make run
python -m project
oh, what up?
(poetry-python-project-py3.11) michaelp@MacBook-Air-3 python_project_template %