fix: allow None as valid input via add in generic_adder

[Pablu23]

Description

generic_adder: allow None as valid input via add

Assignee

• The changes adhere to the contribution guidelines
• I have performed a self-review of my code
• My changes generate no new warnings (e.g. flake8/mypy/pytest/...) other than deprecations

Documentation

• README.md is up-to-date
• CHANGELOG.md is up-to-date
• Documentation (doc/source) is up-to-date
• Preview for docs looks fine
• Notebooks are up-to-date and functional
• Examples are up-to-date and functional (including compose & k8s)

Code Quality

• Patch test coverage > 95% and does not decrease
• New code uses correct & specific type hints

How did you verify that the changes work in practice?

• Tests

Reviewer

• The code is readable/maintainable and follows the contribution guidelines
• Documentation is up-to-date
• Tests (unit & acceptance) are meaningful and not over-mocked

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The rendered docs for this PR can be found here.

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The rendered docs for this PR can be found here.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.15%. Comparing base (ce970b7) to head (c071100).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1010      +/-   ##
==========================================
- Coverage   93.16%   93.15%   -0.02%     
==========================================
  Files         234      234              
  Lines       16070    16086      +16     
==========================================
+ Hits        14972    14985      +13     
- Misses       1098     1101       +3     

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[mhoff]

And please update the PR description. Then we are ready to go

[mhoff]

LGTM. I have checked the preview box as it looks fine and your patch coverage is > 95% ("All modified and coverable lines are covered by tests.")