Follow-up to conclusions from gh-129352, closes gh-85795.
In #129352 (comment), @rhettinger and I agreed that a clear error message is needed when a user attempts to use super() in typing.NamedTuple subclasses.
I believe this PR should be backported. Since we no longer raise a RuntimeError, this cannot be backported.
About the PR
Pure presence of __classcell__ is enough to confirm that __class__ closure was created to enable super() calls.
Tests for cases where __classcell__ are manually set in typed named tuples were intentionally not added, as I don't see the value in considering these behaviors.
Interestingly, I used a note admonition instead of No longer true, we raise .. versionchanged:: next in the docs and it's completely backward-compatible: it applies to all relevant previous versions of Python. I considered making an "important" block instead, but I think super() is not often enough to support that idea.TypeError instead of RuntimeError
CC previous reviewers: @ZeroIntensity @AlexWaygood @JelleZijlstra @rhettinger
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