Update UI testcases

[YangJiao0817]

1. Update copy test case to add retries
2. Updata P2P Preheat test case to waiting
3. Update the Replication new rule button xpath

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Merging #18491 (a85c205) into main (5791f0c) will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main   #18491      +/-   ##
==========================================
- Coverage   67.40%   67.37%   -0.04%     
==========================================
  Files         984      984              
  Lines      106980   106980              
  Branches     2670     2670              
==========================================
- Hits        72109    72073      -36     
- Misses      30991    31027      +36     
  Partials     3880     3880              

Flag	Coverage Δ
unittests	67.37% <ø> (-0.04%)	⬇️

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see 10 files with indirect coverage changes

[chlins]

lgtm