fix: make_static_property_type()

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Update make_static_property_type() to make it compatible with Python 3.13: set Py_TPFLAGS_MANAGED_DICT flag before calling PyType_Ready().

Description

Suggested changelog entry:

Update ``make_static_property_type()`` to make it compatible with Python 3.13.

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Oh. pypy-3.9 does crash:

Fatal Python error: Segmentation fault

Stack (most recent call first, approximate line numbers):
  File "/opt/hostedtoolcache/PyPy/3.9.18/x64/lib/pypy3.9/site-packages/_pytest/assertion/rewrite.py", line 354 in _rewrite_test
  File "/opt/hostedtoolcache/PyPy/3.9.18/x64/lib/pypy3.9/site-packages/_pytest/assertion/rewrite.py", line 146 in exec_module

Last week, the job passed successfully on the master branch: https://github.com/pybind/pybind11/actions/runs/7124039145/job/19397679040

So I suppose that PyPy doesn't like my change.

[rwgk]

From #4970:

which sets the Py_TPFLAGS_MANAGED_DICT flag after calling PyType_Ready().

That seems extremely obviously wrong (in hindsight)? — I don't think we need a reproducer for this issue.

So I suppose that PyPy doesn't like my change.

It was just a flake: I simply triggered a rerun and it worked. — I'm not sure if I've seen that exact flake before, but the successful rerun is all we need to move on here.

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It was just a flake: I simply triggered a rerun and it worked.

Oh, that's surprising, but ok. Thanks for merging my fix.