The PostCommit Python Examples Spark job is flaky

[github-actions]

The PostCommit Python Examples Spark is failing over 50% of the time.
Please visit https://github.com/apache/beam/actions/workflows/beam_PostCommit_Python_Examples_Spark.yml?query=is%3Afailure+branch%3Amaster to see all failed workflow runs.
See also Grafana statistics: http://metrics.beam.apache.org/d/CTYdoxP4z/ga-post-commits-status?orgId=1&viewPanel=8&var-Workflow=PostCommit%20Python%20Examples%20Spark

[github-actions]

This issue has been marked as stale due to 150 days of inactivity. It will be closed in 30 days if no further activity occurs. If you think that’s incorrect or this issue still needs to be addressed, please simply write any comment. If closed, you can reopen the issue at any time. Thank you for your contributions.