cdc: add hex encoding to csv

[CharlesCheung96]

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

• This PR is translated from: cdc: add hex encoding to csv docs-cn#14692
• 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]

[LGTM Timeline notifier]

Timeline:

• 2023-08-04 11:51:40.437164397 +0000 UTC m=+445384.379512920: ☑️ agreed by ran-huang.
• 2023-08-07 02:23:08.29585279 +0000 UTC m=+670472.238201320: ☑️ agreed by qiancai.

[qiancai]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: qiancai

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #14853.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #14854.