SNOW-1874368: Skip snowflake_cortex_sentiment doctest in gcp

[sfc-gh-lmukhopadhyay]

1. Which Jira issue is this PR addressing? Make sure that there is an accompanying issue to your PR.

   Fixes SNOW-1874368 and failing daily precommit test.
   Daily test result with no snowflake_cortex_sentiment failures: https://github.com/snowflakedb/snowpark-python/actions/runs/12658208865/job/35274782725

2. Fill out the following pre-review checklist:

   • I am adding a new automated test(s) to verify correctness of my new code
     • If this test skips Local Testing mode, I'm requesting review from @snowflakedb/local-testing
   • I am adding new logging messages
   • I am adding a new telemetry message
   • I am adding new credentials
   • I am adding a new dependency
   • If this is a new feature/behavior, I'm adding the Local Testing parity changes.
   • I acknowledge that I have ensured my changes to be thread-safe. Follow the link for more information: Thread-safe Developer Guidelines

3. Please describe how your code solves the related issue.

Fix for daily precommit test snowflake_cortex_sentiment doctest failures (Snowpark python daily github action test)

[sfc-gh-jrose]

These examples end up in our public facing docs. I'm not sure we want to have conditionals like this show up there.

[sfc-gh-lmukhopadhyay]

@sfc-gh-jrose In that case, it might be better to remove this docstring example entirely