Add typing_extensions as a main dependency

[mikeprosserni]

• This contribution adheres to CONTRIBUTING.md.

What does this Pull Request accomplish?

This adds an explicit dependency on typing_extensions.

Why should this Pull Request be merged?

When I tried to use the latest version of nitypes in the nidaqmx repo, I got this error when running tests with Python 3.11+:

.venv\Lib\site-packages\nitypes\waveform\_analog.py:8: in <module>
    from typing_extensions import TYPE_CHECKING, TypeVar, final, override
E   ModuleNotFoundError: No module named 'typing_extensions'

I think the upgrade to poetry 2.1 changed how the typing_extensions dependency works. For older versions of Python, it's still implicitly provided, but for the newer versions, it isn't. But since _analog.py is trying to import the typing_extensions module, I think it makes sense for nitypes to explicitly list it as a dependency so that is guaranteed to be available.

What testing has been done?

I'm hoping this change would fix the issue in nidaqmx without nidaqmx having to explicitly depend on typing_extensions, but I don't know how to test that before submitting this PR.

(Note: I went ahead and added the typing_extensions dependency to nidaqmx, so this PR isn't actually needed for that, although it might be a good idea regardless?)

[github-actions]

Test Results

    44 files  ±0      44 suites  ±0   22m 29s ⏱️ + 1m 18s
 2 190 tests ±0   2 190 ✅ ±0  0 💤 ±0  0 ❌ ±0 
49 738 runs  ±0  49 738 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit c0ed792. ± Comparison against base commit ccb12f3.

♻️ This comment has been updated with latest results.

[bkeryan]

I think the upgrade to poetry 2.1 changed how the typing_extensions dependency works. For older versions of Python, it's still implicitly provided, but for the newer versions, it isn't.

If that happens, it's because one of dependencies conditionally depends on it. We can't rely on that.

The other reason it gets installed is for mypy and pyright.