ci: clean up the E2E test environment

[bzp2010]

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?

Clean up the E2E test environment, the following are the changes.

• Reduce the number of ETCD nodes. (multi-node capability not currently in use)
• Upgrade APISIX version
• Update upstream configuration (implementing a TCP/UDP server for testing purposes via OpenResty, it will be replaced with a server in another PR fix: stream route testcase CI failed frequent #2224)

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

[codecov-commenter]

Codecov Report

Merging #2225 (23eb3f2) into master (ebf381d) will increase coverage by 1.69%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2225      +/-   ##
==========================================
+ Coverage   68.13%   69.83%   +1.69%     
==========================================
  Files         127      184      +57     
  Lines        3352     7257    +3905     
  Branches      824      824              
==========================================
+ Hits         2284     5068    +2784     
- Misses       1068     1896     +828     
- Partials        0      293     +293     

Flag	Coverage Δ
backend-e2e-test	44.81% <ø> (?)
backend-e2e-test-ginkgo	51.01% <ø> (?)
backend-unit-test	49.16% <ø> (?)
frontend-e2e-test	67.95% <ø> (-0.18%)	⬇️

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	66.86% <0.00%> (-3.49%)	⬇️
api/internal/core/store/store_mock.go	0.00% <0.00%> (ø)
api/internal/handler/data_loader/route_export.go	75.00% <0.00%> (ø)
api/internal/filter/schema.go	56.00% <0.00%> (ø)
api/internal/handler/handler.go	79.31% <0.00%> (ø)
api/internal/core/server/server.go	61.70% <0.00%> (ø)
api/internal/log/log.go	60.00% <0.00%> (ø)
api/internal/core/store/storehub.go	72.59% <0.00%> (ø)
api/internal/core/entity/entity.go	90.90% <0.00%> (ø)
api/internal/handler/stream_route/stream_route.go	67.53% <0.00%> (ø)
... and 48 more

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