The prompt information of rerere needs to be optimized.

[Mini256]

Bug Report

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

What is expected?

We need more friendly prompt information to let developers know the running status of rerere:

1. 'Waiting previous PRs merged' can be prompted on the CI status during the rerere wait PR merge
2. .rerere.json file needs to be formatted
3. The message body of retesting commit should be refined

What is actually happening?

At present, the prompt information of rere is somewhat difficult to view.

[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.
If this issue is safe to close now please do so with /close.
Send feedback to sig-community-infra or Mini256.
/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