[DOP-13337] Add Pydantic v2 support

[dolfinus]

Change Summary

Related issue number

Allow using onETL with both Pydantic v1 and v2. Thank to Pydantic v2 compatibility layer from pydantic.v1 import ....

Updated CI workflows to include Pydantic version in test matrix.

A lot of lines were changed, but this is mostly copy-paste.

Checklist

• Commit message and PR title is comprehensive
• Keep the change as small as possible
• Unit and integration tests for the changes exist
• Tests pass on CI and coverage does not decrease
• Documentation reflects the changes where applicable
• docs/changelog/next_release/<pull request or issue id>.<change type>.rst file added describing change
  (see CONTRIBUTING.rst for details.)
• My PR is ready to review.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.28%. Comparing base (a994486) to head (6758359).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #230      +/-   ##
===========================================
+ Coverage    94.12%   94.28%   +0.16%     
===========================================
  Files          204      204              
  Lines         7841     8012     +171     
  Branches      1401     1401              
===========================================
+ Hits          7380     7554     +174     
+ Misses         336      334       -2     
+ Partials       125      124       -1     

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