request response route buffering

[shaneutt]

What this PR does / why we need it:
The request_buffering and response_buffering options were added in Kong/kong#6057 and enable users to disable buffering for use cases which call for it (namely, large payloads using HTTP 1.1 chunked encoding).

This PR adds request_buffering and response_buffering options to KongIngress and Ingress annotations.

Which issue this PR fixes
fixes #924

Special notes for your reviewer:

• This requires request response route buffering go-kong#15 as is blocked until that lands in a release.
• still WIP while I'm working on tests

[rainest]

My overview omitted details on the tests usually added for these. This should have them also, for annotation extraction and overriding. Examples of those can be found at:

https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/annotations/annotations_test.go#L310-L340 (for extraction)

https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/controller/parser/kongstate/route_test.go#L408-L494 (for annotation overrides) and https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/controller/parser/kongstate/route_test.go#L35-L52 (for KongIngress overrides).

[codecov]

Codecov Report

Merging #1011 (f5b000d) into main (daa9afa) will decrease coverage by 0.15%.
The diff coverage is 30.76%.

@@            Coverage Diff             @@
##             main    #1011      +/-   ##
==========================================
- Coverage   49.56%   49.41%   -0.16%     
==========================================
  Files          32       32              
  Lines        3198     3224      +26     
==========================================
+ Hits         1585     1593       +8     
- Misses       1483     1499      +16     
- Partials      130      132       +2     

Impacted Files	Coverage Δ
internal/ingress/annotations/annotations.go	82.75% <0.00%> (-6.14%)	⬇️
...ernal/ingress/controller/parser/kongstate/route.go	83.61% <36.36%> (-6.71%)	⬇️

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[shaneutt]

My overview omitted details on the tests usually added for these. This should have them also, for annotation extraction and overriding. Examples of those can be found at:

https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/annotations/annotations_test.go#L310-L340 (for extraction)

https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/controller/parser/kongstate/route_test.go#L408-L494 (for annotation overrides) and https://github.com/Kong/kubernetes-ingress-controller/blob/1.1.0/internal/ingress/controller/parser/kongstate/route_test.go#L35-L52 (for KongIngress overrides).

Sorry, I'm still work in progress so I was reviewing my own work first, and as per the description I'm still adding tests so those will come soon I had not forgotten them 👍

[shaneutt]

I'm going to close this for now because I realize that I have reviewers requested, but this draft is still a work in progress and I don't need review just yet so I don't want anyone to spend time unnecessarily.