Fix implicit Optional [t-z]

[cdce8p]

Proposed change

Mypy will soon make no_implicit_optional the default behavior. Currently, it's only applied together with strict typing.
This PR updates existing integrations to mention None explicitly. Once done, I'll open a follow up PR to set no_implicit_optional for all files.

def f(
-    var: int = None
+    var: int | None = None
) -> None:
    ...

See:
python/mypy#9091
python/mypy#13401

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
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Checklist

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[lymanepp]

LGTM

[epenet]

LGTM