Do not error in pvc_modifier, when a manual TiKV eviction is requested.

[anish-db]

What problem does this PR solve?

pvc_modifier keeps throwing errors even if a manual TiKV region leader eviction is requested by annotating the pod per the documentation here:
https://docs.pingcap.com/tidb-in-kubernetes/stable/maintain-a-kubernetes-node#evict-tikv-region-leader

This happens even if no volume modification is actually requested.

What is changed and how does it work?

Do not keep checking if eviction has ended during pvc_modifier sync.
If an annotation does exist for resize, delete it and throw an error once alone to give pod_control.go a chance to stop the eviction. But do not block forever until it is removed as this may have been requested by user manually and should not throw errors.

Code changes

• Has Go code change
• Has CI related scripts change

Tests

• Unit test
• E2E test
• Manual test
• No code

Side effects

• Breaking backward compatibility
• Other side effects:

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release Notes

Please refer to Release Notes Language Style Guide before writing the release note.

Fix spurious errors from pvc_modifier when manual TiKV eviction is requested by user annotation

[codecov-commenter]

Codecov Report

Merging #5302 (1442543) into master (4df3649) will decrease coverage by 0.05%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5302      +/-   ##
==========================================
- Coverage   57.48%   57.44%   -0.05%     
==========================================
  Files         252      252              
  Lines       30594    30593       -1     
==========================================
- Hits        17586    17573      -13     
- Misses      11271    11278       +7     
- Partials     1737     1742       +5     

Flag	Coverage Δ
unittest	57.44% <ø> (-0.05%)	⬇️

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: csuzhangxc

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• OWNERS [csuzhangxc]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-09-27 06:48:14.096284329 +0000 UTC m=+430283.814626544: ☑️ agreed by csuzhangxc.
• 2023-09-27 06:48:55.43293563 +0000 UTC m=+430325.151277846: ✖️🔁 reset by ti-chi-bot[bot].

[ti-chi-bot]

New changes are detected. LGTM label has been removed.

[csuzhangxc]

/cherry-pick release-1.5

[ti-chi-bot]

@csuzhangxc: new pull request created to branch release-1.5: #5307.

In response to this:

/cherry-pick release-1.5

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