Support ExtensionArray in hash_pandas_object

[TomAugspurger]

Closes #23066

[pep8speaks]

Hello @TomAugspurger! Thanks for submitting the PR.

• There are no PEP8 issues in the file pandas/core/arrays/base.py !

• There are no PEP8 issues in the file pandas/core/util/hashing.py !

• There are no PEP8 issues in the file pandas/tests/extension/base/base.py !

• There are no PEP8 issues in the file pandas/tests/extension/base/methods.py !

• There are no PEP8 issues in the file pandas/tests/extension/json/test_json.py !

[jreback]

lgtm.

[codecov]

Codecov Report

Merging #23082 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master   #23082      +/-   ##
==========================================
+ Coverage   92.19%   92.19%   +<.01%     
==========================================
  Files         169      169              
  Lines       50911    50914       +3     
==========================================
+ Hits        46939    46942       +3     
  Misses       3972     3972

Flag	Coverage Δ
#multiple	90.61% <100%> (ø)	⬆️
#single	42.3% <50%> (-0.01%)	⬇️

Impacted Files	Coverage Δ
pandas/core/arrays/base.py	95.89% <ø> (ø)	⬆️
pandas/core/util/hashing.py	98.4% <100%> (+0.03%)	⬆️

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[jreback]

thanks!