dumpling: add a note about compression

[hfxsd]

What is changed, added or deleted? (Required)

Add a note about the --compress option for dumpling. See pingcap/dumpling#4 (comment) for more details.

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What is the related PR or file link(s)?

• This PR is translated from:dumpling: add a note about compression docs#6619
• Other reference link(s):

Do your changes match any of the following descriptions?

• Delete files
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• Need modification after applied to another branch
• Might cause conflicts after applied to another branch

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• shichun-0415

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[dveeden]

LGTM, but as I have to rely on a translation I can't really do a proper review.

[shichun-0415]

LGTM

[hfxsd]

/merge

[ti-chi-bot]

@hfxsd: /merge in this pull request requires 2 approval(s).

In response to this:

/merge

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[hfxsd]

/merge

[ti-chi-bot]

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

Commit hash: 267b32c

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8743.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8744.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8745.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8746.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8747.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8748.