restore: add faq for rule not found

[3pointer]

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What is changed, added or deleted? (Required)

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By default, CHOOSE MASTER ONLY so your changes will be applied to the next TiDB major or minor releases. If your PR involves a product feature behavior change or a compatibility change, CHOOSE THE AFFECTED RELEASE BRANCH(ES) AND MASTER.

For details, see tips for choosing the affected versions (in Chinese).

• master (the latest development version)
• v7.2 (TiDB 7.2 versions)
• v7.1 (TiDB 7.1 versions)
• v7.0 (TiDB 7.0 versions)
• v6.6 (TiDB 6.6 versions)
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• Delete files
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[ti-chi-bot]

@Leavrth: adding LGTM is restricted to approvers and reviewers in OWNERS files.

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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 kubernetes/test-infra repository.

[ran-huang]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ran-huang

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-5.3: #15724.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.1: #15725.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #15734.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.4: #15736.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-5.4: #15737.

[RobertCheng-956]

/assign

[RobertCheng-956]

/remove-translation welcome

[RobertCheng-956]

/translation done