update regexp docs

[xzhangxian1008]

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• This PR is translated from: update regexp compability docs-cn#11344
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[ti-chi-bot]

[REVIEW NOTIFICATION]

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[Oreoxmt]

Rest LGTM

[Oreoxmt]

@windtalker PTAL

[windtalker]

LGTM

[Oreoxmt]

LGTM

[shichun-0415]

LGTM

[Oreoxmt]

/merge

[ti-chi-bot]

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

Commit hash: 095218d