[Docs] Add the K8s agent set up document (#6184) #5971

Job	Run time
unpack-envvars	1s
flyteadmin integration tests image / build_docker	5m 14s
Build Images / Build & Push Image (datacatalog) / Push to Github Registry	4m 21s
Build Images / Build & Push Image (flyteadmin) / Push to Github Registry	7m 1s
Build Images / Build & Push Image (flytecopilot) / Push to Github Registry	4m 22s
Build Images / Build & Push Image (flytescheduler) / Push to Github Registry	1m 20s
Build Images / Build & Push Image (flytepropeller) / Push to Github Registry	6m 41s
Dry Run Goreleaser	7m 33s
Test Getting started	4m 5s
Check Go Generate (datacatalog) / Go Generate	1m 45s
Check Go Generate (flyteadmin) / Go Generate	2m 24s
Check Go Generate (flytecopilot) / Go Generate	1m 33s
Check Go Generate (flytectl) / Go Generate	2m 13s
Check Go Generate (flytepropeller) / Go Generate	2m 14s
Lint (datacatalog) / Run Lint	2m 34s
Lint (flyteadmin) / Run Lint	3m 41s
Lint (flytecopilot) / Run Lint	2m 0s
Lint (flytectl) / Run Lint	2m 37s
Lint (flyteidl) / Run Lint	1m 55s
Lint (flytepropeller) / Run Lint	3m 12s
Unit Tests (datacatalog) / Run Unit Test	2m 54s
Lint (flytestdlib) / Run Lint	2m 47s
Lint (flyteplugins) / Run Lint	3m 8s
Unit Tests (flyteadmin) / Run Unit Test	4m 49s
Unit Tests (flytecopilot) / Run Unit Test	2m 36s
Unit Tests (flytectl) / Run Unit Test	3m 40s
Unit Tests (flytepropeller) / Run Unit Test	4m 14s
Unit Tests (flytestdlib) / Run Unit Test	3m 38s
Unit Tests (flyteplugins) / Run Unit Test	4m 4s
Integration Test (flyteadmin) / Integration tests	6m 5s
	1h 44m 41s

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