feat: add gzip global setting in configmap

[2456868764]

Ⅰ. Describe what this PR did

add gzip global setting in configmap

Ⅱ. Does this pull request fix one issue?

fixes #410

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[codecov-commenter]

Codecov Report

Merging #660 (f6a2b8e) into main (324e0bc) will decrease coverage by 2.08%.
Report is 16 commits behind head on main.
The diff coverage is 41.89%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #660      +/-   ##
==========================================
- Coverage   36.00%   33.93%   -2.08%     
==========================================
  Files          73       78       +5     
  Lines       10339    11191     +852     
==========================================
+ Hits         3723     3798      +75     
- Misses       6330     7099     +769     
- Partials      286      294       +8     

Files	Coverage Δ
pkg/ingress/kube/configmap/config.go	0.00% <0.00%> (ø)
pkg/ingress/kube/configmap/tracing.go	0.00% <0.00%> (ø)
pkg/ingress/kube/configmap/controller.go	0.00% <0.00%> (ø)
pkg/ingress/kube/configmap/gzip.go	42.66% <42.66%> (ø)

... and 13 files with indirect coverage changes

[johnlanni]

@2456868764 需要补充一下UT和e2e测试

[johnlanni]

#703

可以基于这个实现一下e2e test

[2456868764]

#703

可以基于这个实现一下e2e test

我加了 UT 和 e2e 测试， e2e 测试是根据返回头 content-encoding": "gzip" 来判断，测试了 MinContentLength 和 Content Type，满足e2e 测试要求。 加 envoy配置测试要等到 #703 这个issue 好才加

[johnlanni]

LGTM