Fix ansible module dependencies

[arianvp]

What we were doing before was way too complicated. Ansible itself
doesn't have any dependency on boto to function. The target host
needs to have boto installed.

In our case the target host is 'localhost'. Ansible will by default
pick /usr/bin/python3 as the python interpreter ogit n target hosts but of
course we can't rely on that having boto installed.

Instead, we configure ansible_python_interpreter to point to the
environment we built with nix; which contains a python that has boto
installed.

This way boto can be found and the playbooks should succeed!

[lucendio]

LGTM but DH action for macos does not agree.

[arianvp]

This fixes it locally but it's still broken in the dockerfile. I'll try to get that to work Tuesday first.

[arianvp]

I tested this with the following playbook:

- hosts: localhost
  gather_facts: yes
  serial: 1
  become: no
  tasks:
    - debug: var=ansible_python_interpreter
    - debug: var=ansible_python_version
    - debug: var=ansible_playbook_python
    - aws_s3:
        mode: list
        bucket: public.wire.com

PLAY [localhost] *************************************************************************************************************

TASK [Gathering Facts] *******************************************************************************************************
ok: [localhost]

TASK [debug] *****************************************************************************************************************
ok: [localhost] => {
    "ansible_python_interpreter": "$LOCALHOST_PYTHON"
}

TASK [debug] *****************************************************************************************************************
ok: [localhost] => {
    "ansible_python_version": "3.8.8"
}

TASK [debug] *****************************************************************************************************************
ok: [localhost] => {
    "ansible_playbook_python": "/nix/store/yl69v76azrz4daiqksrhb8nnmdiqdjg9-python3-3.8.8/bin/python3.8"
}

TASK [aws_s3] ****************************************************************************************************************
ok: [localhost]

PLAY RECAP *******************************************************************************************************************
localhost                  : ok=5    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   

[wpcarro]

drive-by comment (feel free to ignore) this is a nice .envrc and Nix pattern :)