feat(kuma-cp): reachable services in transparent proxying

[jakubdyszkiewicz]

Summary

Introduce reachable service. This way, a service owner can restrict which services are reachable from their service.
The result is that Envoy follows only this couple of services which dramatically improves the performance of the system.

Issues resolved

Fix #3779

Documentation

• docs(networking) rewrite transparent proxy and dns kuma-website#671

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

[codecov-commenter]

Codecov Report

Merging #3791 (865b60f) into master (a931aba) will increase coverage by 0.02%.
The diff coverage is 45.45%.

@@            Coverage Diff             @@
##           master    #3791      +/-   ##
==========================================
+ Coverage   55.86%   55.89%   +0.02%     
==========================================
  Files         897      897              
  Lines       53297    53326      +29     
==========================================
+ Hits        29773    29805      +32     
+ Misses      21151    21147       -4     
- Partials     2373     2374       +1     

Impacted Files	Coverage Δ
api/mesh/v1alpha1/dataplane.pb.go	36.92% <0.00%> (-0.29%)	⬇️
pkg/plugins/runtime/k8s/metadata/annotations.go	100.00% <ø> (ø)
pkg/xds/sync/dataplane_proxy_builder.go	65.33% <0.00%> (-6.73%)	⬇️
...est/framework/deployments/testserver/deployment.go	0.00% <0.00%> (ø)
...est/framework/deployments/testserver/kubernetes.go	0.00% <0.00%> (ø)
test/framework/interface.go	0.00% <0.00%> (ø)
test/framework/setup.go	3.16% <0.00%> (ø)
test/framework/universal_app.go	0.00% <ø> (ø)
api/mesh/v1alpha1/dataplane_helpers.go	86.02% <100.00%> (ø)
pkg/core/resources/apis/mesh/dataplane_helpers.go	87.32% <100.00%> (+2.18%)	⬆️
... and 15 more

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[lahabana]

I have one slightly concern WRT Universal and Outbounds but I'm unsure.