dm: fix capitalization in heading

[ran-huang]

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[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Oreoxmt

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[Oreoxmt]

LGTM

[ran-huang]

/merge

[ti-chi-bot]

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

Commit hash: 46c45ed

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #11322.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #11323.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #11324.