Fix doctest for get_protocol_members

[JanEricNitschke]

Dicovered by running Cpython 3.12 test_typing.py on typing_extensions: https://github.com/JanEricNitschke/typing_extensions/actions/runs/17693805118/job/50290793287#step:7:115

"New" doctest from here: https://github.com/python/cpython/blob/805e3368d6d07e58430654d1365283924fdf4143/Lib/typing.py#L3737

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.37%. Comparing base (9215c95) to head (9a77b15).
⚠️ Report is 1 commits behind head on main.

@@           Coverage Diff           @@
##             main     #680   +/-   ##
=======================================
  Coverage   97.36%   97.37%           
=======================================
  Files           3        3           
  Lines        7680     7684    +4     
=======================================
+ Hits         7478     7482    +4     
  Misses        202      202           

Flag	Coverage Δ
3.10	89.00% <100.00%> (+<0.01%)	⬆️
3.10.4	89.00% <100.00%> (+<0.01%)	⬆️
3.11	88.23% <100.00%> (?)
3.11.0	87.46% <100.00%> (+<0.01%)	⬆️
3.12	88.18% <100.00%> (+<0.01%)	⬆️
3.12.0	88.16% <100.00%> (+<0.01%)	⬆️
3.13	82.40% <100.00%> (?)
3.13.0	82.40% <100.00%> (+<0.01%)	⬆️
3.14	78.84% <100.00%> (+0.01%)	⬆️
3.9	89.71% <100.00%> (+<0.01%)	⬆️
3.9.12	89.71% <100.00%> (+<0.01%)	⬆️
pypy3.10	88.83% <100.00%> (+<0.01%)	⬆️
pypy3.11	88.09% <100.00%> (+<0.01%)	⬆️
pypy3.9	89.54% <100.00%> (+<0.01%)	⬆️

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Files with missing lines	Coverage Δ
src/test_typing_extensions.py	98.39% <100.00%> (+<0.01%)	⬆️
src/typing_extensions.py	93.88% <ø> (ø)

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[AlexWaygood]

Cpython runs these doctests in CI but I'm not sure we do — might be worth it for us to do the same?

[JanEricNitschke]

Cpython runs these doctests in CI but I'm not sure we do — might be worth it for us to do the same?

Done