clarify the meaning of small transaction for TTL

[qiancai]

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• This PR is translated from: Clarify the meaning of small transaction for TTL docs-cn#8564
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[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• TomShawn

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[TomShawn]

rest LGTM

[qiancai]

/remove-status LGT1
/status LGT2

[qiancai]

/merge

[ti-chi-bot]

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

Commit hash: 570b23e

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #10663.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #10664.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #10665.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #10666.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #10667.