Tooling updates

[zerolab]

• update ruff to 0.3.x, tidy up config
• use ruff for formatting (and drop black)
• lint
• move nightly tests to GHA
• add a publish action

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 82.85714% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 93.03%. Comparing base (cf12512) to head (089839b).

Files	Patch %	Lines
wagtail_localize/models.py	68.42%	5 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #790      +/-   ##
==========================================
+ Coverage   92.83%   93.03%   +0.19%     
==========================================
  Files          47       47              
  Lines        4148     4132      -16     
  Branches      605      701      +96     
==========================================
- Hits         3851     3844       -7     
+ Misses        176      173       -3     
+ Partials      121      115       -6     

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