Remove some desc

[glkappe]

This logic was removed in version 3.0.19 and does not exist in subsequent versions, please release the time through v3.0.19

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Do your changes match any of the following descriptions?

• Delete files
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• Might cause conflicts after applied to another branch

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• TomShawn

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After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

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[glkappe]

**
tikv/pd#1607**

@TomShawn

[ti-chi-bot]

@HunDunDM: Thanks for your review. The bot only counts approvals from reviewers and higher roles in list, but you're still welcome to leave your comments.

In response to this:

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[ti-chi-bot]

@HunDunDM: Thanks for your review. The bot only counts approvals from reviewers and higher roles in list, but you're still welcome to leave your comments.

In response to this:

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[TomShawn]

/remove-status LGT1
/status LGT2

[TomShawn]

/merge

[ti-chi-bot]

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

Commit hash: 492af30

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6919.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6920.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6921.