[CI]: Consider More Detailed JinJa2 Template Linting and Checking

[BethanyG]

After doing numerous JinJa2 template PRs and test file regeneration (and getting caught by a nasty indentation bug), it feels like we could benefit from setting up some linting rules and checks for JinJa2 templates that are a bit more detailed and custom. Right now, we check that the files will produce test files that can be linted by Black, but we don't really do much additional validation.

Marking this as a discussion, since I haven't formed many more thoughts that that around this issue. But I anticipate both more contributors and more changes to templates going forward, so thought I'd make a note here of what I have found so far:

curlylint
Jinjalint

[github-actions]

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