Enable warnings as errors for weekly run in test suite

[mlxd]

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Context: This PR enables a weekly run of the test suite with Python-level warnings promoted to errors (exceptions). This will allow the test suite to regularly report when hitting warnings through general execution.

Description of the Change: Add a new workflow to run the test suite with Python warnings as errors on a weekly basis,

Benefits: Enable us to catch warnings when and where they occur during testing.

Possible Drawbacks: Additional overhead of running the CI at the intended occurrence.

Related GitHub Issues:

[mudit2812]

Looks good. Left a bunch of suggestions. I would also suggest adding a pull_request trigger to the workflow once it's reasonably complete so you can test it out in action before the PR gets merged.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.58%. Comparing base (060bb9a) to head (01df56b).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6217      +/-   ##
==========================================
- Coverage   99.59%   99.58%   -0.02%     
==========================================
  Files         444      443       -1     
  Lines       42321    42230      -91     
==========================================
- Hits        42149    42053      -96     
- Misses        172      177       +5     

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[mudit2812]

Couple of more changes to tidy up the workflow, but functionally looks great!

[mudit2812]

Looks good. We have an epic for next quarter with stories for updating workflows. I'll add a story there to implement the suggestions in this PR that are not able to be done right now.

[mlxd]

Note: splitting seems to be affected in this PR. Follow-up re-eval needed.

[mudit2812]

Note: splitting seems to be affected in this PR. Follow-up re-eval needed.

Maybe the splits need to be set up in the setup-ci-load step too