[tech debt] Avoid recursive include of DEFAULT_SETTINGS, sanity test

[AlanCoding]

SUMMARY

I told @john-westcott-iv this was going to bother me, but I wasn't going to make a PR to change it until I saw this failure.

Traceback (most recent call last):
  File "/awx_devel/awx/main/tests/unit/test_settings.py", line 22, in test_default_settings
    raise Exception(f'Default setting for {k} does not match:\nsnapshot: {snapshot_val}\ndefault: {default_val}')
Exception: Default setting for DEFAULTS_SNAPSHOT does not match:
...

Wait, what? The snapshot value for DEFAULTS_SNAPSHOT doesn't match? That doesn't make any sense. We got that snapshot value from the snapshot dictionary! Did this dict save a copy of itself... inside itself?

Yes.

ISSUE TYPE

• Bug, Docs Fix or other nominal change

COMPONENT NAME

• API

[AlanCoding]

I wanted to del these because we do use dir on the settings module in our settings wrapper:

https://github.com/ansible/awx/blob/devel/awx/conf/settings.py#L474

and I just don't want to pollute that namespace with more variables that should be internal to logic inside of settings. It would be impractical to add an __ALL__ to this module. Also, the original recursive copy here was because of lack of awareness of what things hanging out in locals(). We avoid copying lowercase vars in the loop, but I prefer to explicitly exclude them from the namespace, as they should not be public.

[AlanCoding]

Integration tests are passing, so I'm happy with this myself now.

[AlanCoding]

@john-westcott-iv I believe I updated based on all your review comments. How does it look now?