Add a description about how to resolve conflict of a cherry-pick PR

[JaySon-Huang]

Feature Request

• I have searched the issues of this repository and believe that this is not a duplicate.

Is your feature request related to a Issue or PR(Optional)

• Which project: All

• PR or Issue Link: session: force tidb_multi_statement_mode=OFF when mode=WARN (#25723) pingcap/tidb#25749

Describe the feature you'd like:

I want a description about how to resolve the conflict of a cherry-pick PR. More explicitly:

• If you have the write access to the cherry-pick branch
  • How to check the cherry-pick PR easily
  • After conflicts are resolved, how to push those commit to the original branch

A further issue maybe:

• If you don't have the write access to the cherry-pick branch, add a description about what you should do

Do you have any ideas on how to implement it?(Optional)

[ti-chi-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.
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/lifecycle stale

[ti-chi-bot]

Stale issues rot after 30d of inactivity.
Mark the issue as fresh with /remove-lifecycle rotten.
Rotten issues close after an additional 30d of inactivity.
If this issue is safe to close now please do so with /close.
Send feedback to sig-community-infra or Mini256.
/lifecycle rotten