fix wrong coprocessor alert rules

[glkappe]

tikv/tikv#10792

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[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• TomShawn

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[TomShawn]

/merge

[ti-chi-bot]

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

Commit hash: ad6452c

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6909.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6910.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #6911.