Add support for RevisionMixin models that are not also DraftStateMixin subclasses

[alexalligator]

Fixes #857

Notes:

• In order to trigger the transaction.on_commit hook in TranslationSource.create_or_update translation I have used a TransactionTestCase.

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.22%. Comparing base (a0aa5b5) to head (6f50989).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #859      +/-   ##
==========================================
+ Coverage   93.13%   93.22%   +0.08%     
==========================================
  Files          47       47              
  Lines        4241     4248       +7     
  Branches      550      551       +1     
==========================================
+ Hits         3950     3960      +10     
+ Misses        174      172       -2     
+ Partials      117      116       -1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[zerolab]

LGTM. Thank you for this. Aiming to make a new release this week