lightning: fix a lightning config bug

[Joyinqin]

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• This PR is translated from: lightning: fix a lightning config bug docs-cn#6484
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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.

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Commit hash: 767e635

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #5837.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #5838.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #5839.