* NET-6945 - Replace usage of deprecated Envoy field envoy.config.core.v3.HeaderValueOption.append
* update proto for v2 and then update xds v2 logic
* add changelog
* Update 20078.txt to be consistent with existing changelog entries
* swap enum values tomatch envoy.
* Fixes issues in setting status
* Update golden files for changes to xds generation to not use deprecated
methods
* Fixed default for validation of JWT for route