[Doc] Explain how Agent Secret Works #4153

Job	Run time
unpack-envvars	1s
flyteadmin integration tests image / build_docker	4m 48s
Build Images / Build & Push Image (datacatalog) / Push to Github Registry	4m 24s
Build Images / Build & Push Image (flyteadmin) / Push to Github Registry	5m 15s
Build Images / Build & Push Image (flytecopilot) / Push to Github Registry	3m 58s
Build Images / Build & Push Image (flytepropeller) / Push to Github Registry	25s
Build Images / Build & Push Image (flytescheduler) / Push to Github Registry	5m 15s
Dry Run Goreleaser	7m 31s
Test Getting started	6m 33s
Unit Tests (datacatalog) / Run Unit Test	2m 28s
Unit Tests (flyteadmin) / Run Unit Test	3m 54s
Unit Tests (flytecopilot) / Run Unit Test	2m 20s
Unit Tests (flytectl) / Run Unit Test	3m 1s
Unit Tests (flyteplugins) / Run Unit Test	3m 35s
Unit Tests (flytepropeller) / Run Unit Test	3m 42s
Check Go Generate (datacatalog) / Go Generate	1m 0s
Check Go Generate (flyteadmin) / Go Generate	1m 58s
Check Go Generate (flytecopilot) / Go Generate	59s
Check Go Generate (flytectl) / Go Generate	1m 22s
Check Go Generate (flytepropeller) / Go Generate	1m 41s
Lint (datacatalog) / Run Lint	2m 5s
Lint (flyteadmin) / Run Lint	2m 38s
Lint (flytectl) / Run Lint	1m 46s
Lint (flyteidl) / Run Lint	1m 29s
Lint (flyteplugins) / Run Lint	2m 20s
Lint (flytepropeller) / Run Lint	2m 41s
Unit Tests (flytestdlib) / Run Unit Test	3m 13s
Lint (flytestdlib) / Run Lint	2m 7s
Integration Test (flyteadmin) / Integration tests	1s
	1h 22m 30s

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