fix(worker): Resolve N+1 queries in ProcessFlakesTask

[sentry]

This PR addresses two N+1 query patterns identified in the app.tasks.flakes.ProcessFlakesTask within services/test_analytics/ta_process_flakes.py.

Changes Made:

1. Batched Testrun Fetching:

   • Introduced get_testruns_for_uploads to fetch all Testrun objects for all relevant ReportSession uploads in a single batched query using upload_id__in.
   • The process_flakes_for_commit function now calls this new function once, then distributes the pre-fetched testruns to process_single_upload.

2. Consolidated Flake Updates:

   • The handle_pass function no longer calls flake.save() individually when a flake expires (reaches 30 passes).
   • Expired flakes are now collected into an expired_flakes list.
   • A single Flake.objects.bulk_update() is performed for all collected expired flakes at the end of process_flakes_for_commit.

3. Consolidated Testrun Updates:

   • The Testrun.objects.bulk_update() call, previously executed per upload, is now consolidated into a single call at the end of process_flakes_for_commit for all modified testruns.

Reasoning:

These changes eliminate the N+1 query issues, significantly improving performance and reducing database load when processing flakes, especially for commits with a large number of uploads or many expiring flakes.

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Fixes WORKER-YYX

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.89%. Comparing base (701e991) to head (e64ca06).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1426      +/-   ##
==========================================
- Coverage   91.89%   91.89%   -0.01%     
==========================================
  Files        1325     1325              
  Lines       50868    50881      +13     
  Branches     1626     1626              
==========================================
+ Hits        46744    46755      +11     
- Misses       3818     3820       +2     
  Partials      306      306              

Flag	Coverage Δ
workerintegration	58.52% <10.00%> (-0.05%)	⬇️
workerunit	90.37% <100.00%> (-0.01%)	⬇️

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[codecov-notifications]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

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