CaseGroups request spec & custom policy generator

[thejonroberts]

What github issue is this PR for, if any?

Addresses #5563

What changed, and why?

• Created request specs for CaseGroups controller (they were allowed-skipped)
• CaseGroupController did not have a policy to use (but everything was built from current_organization)
• Wanted to add a policy generator since the pundit:policy generator is so minimal
• Created a CaseGroup policy (and spec), and refined generator based on that
• Incorporate a policy into the controller, as used in other routes
• Created hooks for rails controller and scaffold generators to ensure a policy is generated along with them

How is this tested? (please write tests!) 💖💪

The request spec was created with the controller as-is, and made to pass.

Then the policy changes were made in the controller without changing specs -- with one exception: The update action redirected to new rather than traditional edit redirect. I made that change.

NOTES:

• This commit contains the changes from generated policy to make policy spec pass.
• I also made some custom scaffold and controller request spec templates, but that may be too much to include here, I will open a separate PR for those.

Screenshots please :)

Policy generator help:

Feelings gif (optional)

[elasticspoon]

Ahhhhhh. never mind I am silly I can just do rails g policy some_action