util: split the tests of workloadrepo into multiple shard

[winoros]

What problem does this PR solve?

Issue Number: ref #58247

Problem Summary:

What changed and how does it work?

In #58266, the timeout was set to long. From https://bazel.build/reference/test-encyclopedia, we can see that the long is 900s, which is too long for a whole dir.
If it really has some tests exceeding the default short threshold, please verify the test first, then consider putting slow ones into a separate dir.

And enable the sharding

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.3223%. Comparing base (36e8e34) to head (b1cbbe8).
Report is 9 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #59030        +/-   ##
================================================
+ Coverage   73.0285%   73.3223%   +0.2937%     
================================================
  Files          1684       1685         +1     
  Lines        465663     467372      +1709     
================================================
+ Hits         340067     342688      +2621     
+ Misses       104691     103731       -960     
- Partials      20905      20953        +48     

Flag	Coverage Δ
integration	42.7917% <ø> (?)
unit	72.2286% <ø> (+0.0168%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	45.3097% <ø> (+0.0777%)	⬆️

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, lance6716

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-01-19 14:10:45.981203 +0000 UTC m=+17173.312122405: ☑️ agreed by hawkingrei.
• 2025-01-19 14:25:23.075404824 +0000 UTC m=+18050.406324225: ☑️ agreed by lance6716.

[winoros]

and the running time of each test:

➜  tidb git:(fix-unexpected-delete) ✗ gotestsum --format testname -- --tags=intest ./pkg/util/workloadrepo/...
PASS pkg/util/workloadrepo.TestRaceToCreateTablesWorker (7.70s)
PASS pkg/util/workloadrepo.TestMultipleWorker (12.92s)
PASS pkg/util/workloadrepo.TestGlobalWorker (8.47s)
PASS pkg/util/workloadrepo.TestAdminWorkloadRepo (4.16s)
PASS pkg/util/workloadrepo.TestSamplingTimingWorker (23.62s)
PASS pkg/util/workloadrepo.TestSnapshotTimingWorker (15.18s)
PASS pkg/util/workloadrepo.TestStoppingAndRestartingWorker (13.48s)
PASS pkg/util/workloadrepo.TestSettingSQLVariables (15.49s)
PASS pkg/util/workloadrepo.TestCreatePartition (3.65s)
PASS pkg/util/workloadrepo.TestDropOldPartitions (1.44s)
PASS pkg/util/workloadrepo.TestAddNewPartitionsOnStart (1.00s)
PASS pkg/util/workloadrepo.TestHouseKeeperThread (17.15s)
[2025/01/19 21:44:02.706 +08:00] [INFO] [manager.go:431] ["etcd session close failed"] [key=workloadrepo] [id=worker] [error="context canceled"]
PASS pkg/util/workloadrepo.TestCalcNextTick (0.00s)
PASS pkg/util/workloadrepo

DONE 13 tests in 134.829s