feat(plugin): allowing limit-req to dynamically adapt to the BE rules

[wmdmomo]

Please answer these questions before submitting a pull request, or your PR will get closed.

Why submit this pull request?

• Bugfix
• New feature provided
• Improve performance
• Backport patches

What changes will this PR take into?

The PR will change the plugin under plugin/UI (limit-req), allowing limit-req to dynamically adapt to the back-end json rules.

Related issues

fix/resolve #1588

Checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

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[codecov-commenter]

Codecov Report

Merging #1995 (8fb5293) into master (0b5196f) will decrease coverage by 0.04%.
The diff coverage is 100.00%.

❗ Current head 8fb5293 differs from pull request most recent head 102c929. Consider uploading reports for the commit 102c929 to get more accurate results

@@            Coverage Diff             @@
##           master    #1995      +/-   ##
==========================================
- Coverage   64.01%   63.97%   -0.05%     
==========================================
  Files         122      122              
  Lines        3154     3156       +2     
  Branches      753      753              
==========================================
  Hits         2019     2019              
- Misses       1135     1137       +2     

Flag	Coverage Δ
frontend-e2e-test	63.97% <100.00%> (-0.05%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
web/src/components/Plugin/PluginDetail.tsx	65.82% <100.00%> (+0.21%)	⬆️
web/src/components/Plugin/UI/limit-req.tsx	100.00% <100.00%> (ø)
web/src/components/Plugin/UI/plugin.tsx	82.60% <100.00%> (ø)
web/src/helpers.tsx	68.85% <0.00%> (-3.28%)	⬇️

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