MINOR: [Docs][Python] Update python_test.cc reference

[emmanuel-ferdman]

Rationale for this change

Commit 21dbf4a moved the location of python_test.cc.

What changes are included in this PR?

PR updates the reference to python_test.cc.

Are these changes tested?

Are there any user-facing changes?

No.

[github-actions]

Thanks for opening a pull request!

If this is not a minor PR. Could you open an issue for this pull request on GitHub? https://github.com/apache/arrow/issues/new/choose

Opening GitHub issues ahead of time contributes to the Openness of the Apache Arrow project.

Then could you also rename the pull request title in the following format?

GH-${GITHUB_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

or

MINOR: [${COMPONENT}] ${SUMMARY}

In the case of PARQUET issues on JIRA the title also supports:

PARQUET-${JIRA_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - Contributing Overview

[github-actions]

⚠️ GitHub issue #44622 has been automatically assigned in GitHub to PR creator.

[kou]

@github-actions crossbow submit preview-docs

[github-actions]

Revision: f9da40b

Submitted crossbow builds: ursacomputing/crossbow @ actions-8c06f1053b

Task	Status
preview-docs

[jorisvandenbossche]

Thanks for the catch!

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 3 benchmarking runs that have been run so far on merge-commit 9b27f42.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 3 possible false positives for unstable benchmarks that are known to sometimes produce them.