[09Catho]

Rationale for this change

Four tests use NumPy but are missing pytest.mark.numpy. Without that marker, the no-NumPy job does not exercise them and the tests can fail with an AttributeError when an off-by-default group runs without NumPy.

What changes are included in this PR?

Add pytest.mark.numpy to the three large-memory conversion tests and the CUDA-backed test_non_cpu_array test named in #55458.

Are these changes tested?

• python -m py_compile python/pyarrow/tests/test_convert_builtin.py python/pyarrow/tests/test_array.py passed.
• An AST check confirmed all four target functions have the NumPy marker.
• git diff --check passed.
• The focused pytest commands could not collect because this shallow source checkout does not contain the generated pyarrow.lib extension. No pytest result is claimed.

Are there any user-facing changes?

No. This only corrects test selection for environments without NumPy.

Was AI used for this PR?

In accordance to the AI generation guidelines, please disclose below whether and how AI was used in this PR.

PR code and description written by:

• Human
• AI

Reviewed before submission by:

• Human
• AI
• Not reviewed

• GitHub Issue: [Python] Some tests that are off by default use NumPy without @pytest.mark.numpy #55458

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has insufficient remaining quota. Try requesting a review at a lower effort level.

[github-actions]

⚠️ GitHub issue #55458 has been automatically assigned in GitHub to PR creator.