DM: add a step about encrypting the database password

[hfxsd]

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[ti-chi-bot]

@Frank945946: adding LGTM is restricted to approvers and reviewers in OWNERS files.

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[qiancai]

Rest LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-06-11 08:14:08.50328706 +0000 UTC m=+452402.556598980: ☑️ agreed by qiancai.

[hfxsd]

/approve

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.0: #17646.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #17647.

[Frank945946]

LGTM