docs: fix format for TiKV and PD configuration file template invalid. (#6197)

[ti-chi-bot]

This is an automated cherry-pick of #6197

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• Closes Format for TiKV and PD configuration file template is invalid. #6145

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[ti-chi-bot]

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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: 09bf75a