GH-40282: [Python] Use C++ type traits for is_nested function

[llama90]

Rationale for this change

Use C++ type traits for is_nested function to avoid redefining in Python

What changes are included in this PR?

Expose is_nested function

Are these changes tested?

Yes

Are there any user-facing changes?

Yes

• GitHub Issue: #40282

[github-actions[bot]]

:warning: GitHub issue #40282 has been automatically assigned in GitHub to PR creator.

[llama90]

@danepitkin Hello.

Does this align with the original intent? I closed the previous PR because there were too many code changes, and I've opened a new one.

Please review it when you have time. Thank you!

[llama90]

@AlenkaF @pitrou Does this align with the original intent? Please review it when you have time. Thank you!