gh-141510: Update PyDict C API doc for frozendict

[vstinner]

Mention frozendict support.

• Issue: PEP 814: Add built-in frozendict type #141510

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📚 Documentation preview 📚: https://cpython-previews--145533.org.readthedocs.build/

[vstinner]

I used test_capi.test_dict to check if PyDict functions accept frozendict or not.

cc @encukou

[encukou]

You've missed PyDict_Contains.

I think the info for the current behaviour should be in the main text, not in the versionchanged directive. If nothing else, there's been a suggestion to hide these for older versions.

[vstinner]

You've missed PyDict_Contains.

Oops, fixed.

I think the info for the current behaviour should be in the main text, not in the versionchanged directive.

I updated the PR to mention frozendict in the main text. I kept versionchanged. I'm not sure if you want both, or only changing the main text.

[vstinner]

@encukou and/or @ZeroIntensity: Do you want to review this change?

[encukou]

Now, do we need versionchanged at all, since frozendict was added in this version?

Suggested change

	.. versionchanged:: next
	Also accept :class:`frozendict`.

[ZeroIntensity]

I think it's nice to have an explicit historical record.

[vstinner]

I prefer to be explicit about the change.

[ZeroIntensity]

LGTM