Validate `resources.request.storage` for each item in `spec.tiflash.storageClaims`

[hoyhbx]

What problem does this PR solve?

This PR solves the problem that assigning empty objects under storageClaims of tiflash can bypass the validation of the operator.

We found that when we specified tiflash spec with some empty objects under storageClaims, we got rejection from the events saying that storage is a required field. However, we did not get error messages or alerts from the operator indicating that storage is required.

Additionally, from the source code of TiDB operator, we discovered that assigning empty objects under storageClaims can bypass the operator's validation code. For details, please refer to the issue we submitted: https://github.com/pingcap/tidb-operator/issues/4613

What is changed and how does it work?

We believed it is necessary to check whether storage is set when specifying storageClaims for tiflash. We added a sanity check in the function validateTiFlashSpec to see whether storage exists in the resource requests.

Code changes

• [x] Has Go code change
• [ ] Has CI related scripts change

Tests

• [x] 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.

Validate `resources.request.storage` for each item in `spec.tiflash.storageClaims`

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• DanielZhangQD
• KanShiori

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[DanielZhangQD]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 6fc27866c0948cbdea5949af417146513ae6b5ec

[codecov-commenter]

Codecov Report

Merging #4635 (b351275) into master (b004b9a) will decrease coverage by 0.01%. The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4635      +/-   ##
==========================================
- Coverage   59.01%   59.01%   -0.01%     
==========================================
  Files         227      227              
  Lines       26357    26357              
==========================================
- Hits        15555    15554       -1     
- Misses       9298     9299       +1     
  Partials     1504     1504              

Flag	Coverage Δ
unittest	59.01% <ø> (-0.01%)	:arrow_down:

[DanielZhangQD]

/run-all-tests

[DanielZhangQD]

/test pull-e2e-kind-across-kubernetes

[DanielZhangQD]

/run-all-tests

[DanielZhangQD]

/run-all-tests

[DanielZhangQD]

/test pull-e2e-kind pull-e2e-kind-serial

[ti-chi-bot]

Merge canceled because a new commit is pushed.

[hoyhbx]

Hi @KanShiori I just rebased it, is it possible for you to take a look and merge this fix?