feat(kuma-cp): upstream validation of Gateway API

[jakubdyszkiewicz]

Summary

Add upstream validation of Gateway API

Issues resolved

Fix #3416

Documentation

- [ ] Link to the website documentation PR

Testing

• Unit tests
• E2E tests
• Manual testing on Universal
• Manual testing on Kubernetes

Backwards compatibility

- [ ] Update UPGRADE.md with any steps users will need to take when upgrading.
- [ ] Add backport-to-stable label if the code follows our backporting policy

Changelog: feat(gateway): release K8s GatewayAPI as preview

[codecov-commenter]

Codecov Report

Merging #4072 (70dd3dc) into master (1ddc1e6) will increase coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #4072      +/-   ##
==========================================
+ Coverage   55.79%   55.82%   +0.02%     
==========================================
  Files         922      922              
  Lines       55443    55446       +3     
==========================================
+ Hits        30937    30951      +14     
+ Misses      22055    22040      -15     
- Partials     2451     2455       +4     

Impacted Files	Coverage Δ
pkg/plugins/runtime/k8s/plugin.go	1.06% <0.00%> (-0.02%)	⬇️
pkg/kds/reconcile/reconciler.go	79.48% <0.00%> (-5.13%)	⬇️
pkg/core/resources/manager/cache.go	85.71% <0.00%> (-2.60%)	⬇️
pkg/xds/generator/direct_access_proxy_generator.go	89.65% <0.00%> (-1.15%)	⬇️
pkg/insights/resyncer.go	74.07% <0.00%> (+2.46%)	⬆️
...s/authn/api-server/tokens/admin_token_bootstrap.go	82.00% <0.00%> (+4.00%)	⬆️
pkg/events/eventbus.go	92.59% <0.00%> (+7.40%)	⬆️
pkg/core/runtime/component/component.go	88.67% <0.00%> (+7.54%)	⬆️
pkg/insights/components.go	100.00% <0.00%> (+30.00%)	⬆️

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