docs: remove some config fields for copr cache (#5699)

[ti-srebot]

cherry-pick #5699 to release-5.0
You can switch your code base to this Pull Request by using git-extras:

# In docs-cn repo:
git pr https://github.com/pingcap/docs-cn/pull/5778

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/docs-cn.git pr/5778:release-5.0-3e9358ec4f58

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Signed-off-by: lzmhhh123 lzmhhh123@gmail.com

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What is changed, added or deleted? (Required)

Which TiDB version(s) do your changes apply to? (Required)

• master (the latest development version)
• v5.0 (TiDB 5.0 versions)
• v4.0 (TiDB 4.0 versions)
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What is the related PR or file link(s)?

• This PR is translated from:
• Other reference link(s): config: deprecate tikv-client.copr-cache.enable and invisible some copr-cache configs tidb#22786

Do your changes match any of the following descriptions?

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

[ti-srebot]

@lzmhhh123 you're already a collaborator in bot's repo.

[TomShawn]

/status DNM

[TomShawn]

/lgtm
/remove-status DNM

[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.

Commit hash: d270c60