Add unit test to cover non built-in GenericAlias types

[jrmccluskey]

Adds a unit test to ensure that parameterized generic types that are not built-in are handled properly by type hinting code.

---

Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily:

• Mention the appropriate issue in your description (for example: addresses #123), if applicable. This will automatically add a link to the pull request in the issue. If you would like the issue to automatically close on merging the pull request, comment fixes #<ISSUE NUMBER> instead.
• Update CHANGES.md with noteworthy changes.
• If this contribution is large, please file an Apache Individual Contributor License Agreement.

See the Contributor Guide for more tips on how to make review process smoother.

To check the build health, please visit https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI.

[jrmccluskey]

R: @damccorm

[codecov]

Codecov Report

Merging #25091 (e1eda50) into master (6203e58) will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #25091      +/-   ##
==========================================
- Coverage   73.12%   73.12%   -0.01%     
==========================================
  Files         735      735              
  Lines       98153    98161       +8     
==========================================
+ Hits        71776    71781       +5     
- Misses      25013    25016       +3     
  Partials     1364     1364              

Flag	Coverage Δ
python	82.67% <ø> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
.../python/apache_beam/testing/test_stream_service.py	88.09% <0.00%> (-4.77%)	⬇️
...apache_beam/typehints/native_type_compatibility.py	82.82% <0.00%> (-2.34%)	⬇️
...che_beam/runners/interactive/interactive_runner.py	90.50% <0.00%> (-1.27%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.17% <0.00%> (-0.38%)	⬇️
sdks/python/apache_beam/transforms/util.py	96.24% <0.00%> (-0.16%)	⬇️
sdks/python/apache_beam/typehints/typehints.py	92.88% <0.00%> (ø)
...on/apache_beam/runners/dataflow/dataflow_runner.py	81.88% <0.00%> (+0.14%)	⬆️
...eam/runners/portability/fn_api_runner/execution.py	93.13% <0.00%> (+0.63%)	⬆️
sdks/python/apache_beam/internal/metrics/metric.py	94.00% <0.00%> (+1.00%)	⬆️
sdks/python/apache_beam/io/source_test_utils.py	89.86% <0.00%> (+1.38%)	⬆️
... and 1 more

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[jrmccluskey]

Portable Python pre-commit passed but failed to update the PR description