The backup cleaner can't clean the CR at the schedule phase before task start (#5967)

[ti-chi-bot]

This is an automated cherry-pick of #5967

What problem does this PR solve?

Close #5968

What is changed and how does it work?

Set the status of the not started CR to stop phase.
The task haven't been started so there will ok to delete it immediately.

Code changes

• Has Go code change
• Has CI related scripts change

Tests

• Unit test
• E2E test
• Manual test
• No code

Side effects

• Breaking backward compatibility
• Other side effects:

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release Notes

Please refer to Release Notes Language Style Guide before writing the release note.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.

Project coverage is 56.98%. Comparing base (c23a794) to head (cbfbd48).
Report is 13 commits behind head on release-1.6.

Additional details and impacted files

@@               Coverage Diff               @@
##           release-1.6    #5971      +/-   ##
===============================================
- Coverage        57.20%   56.98%   -0.22%     
===============================================
  Files              259      260       +1     
  Lines            33233    45033   +11800     
===============================================
+ Hits             19010    25663    +6653     
- Misses           12290    17386    +5096     
- Partials          1933     1984      +51     

Flag	Coverage Δ
unittest	56.98% <0.00%> (-0.22%)	⬇️