Update Propeller architecture documentation #2728

Job	Run time
unpack-envvars	1s
Docker Build Images (datacatalog) / build_docker	2m 20s
Docker Build Images (flyteadmin) / build_docker	3m 4s
Docker Build Images (flytecopilot) / build_docker	2m 2s
Docker Build Images (flytepropeller) / build_docker	2m 58s
Build Images / Build & Push Image (datacatalog) / Push to Github Registry	2m 40s
Build Images / Build & Push Image (flyteadmin) / Push to Github Registry	3m 34s
Build Images / Build & Push Image (flytecopilot) / Push to Github Registry	2m 36s
Build Images / Build & Push Image (flytepropeller) / Push to Github Registry	3m 44s
Build Images / Build & Push Image (flytescheduler) / Push to Github Registry	3m 38s
Check Go Generate (flyteadmin) / Go Generate	2m 31s
Check Go Generate (flytecopilot) / Go Generate	1m 48s
Check Go Generate (datacatalog) / Go Generate	1m 42s
Lint (datacatalog) / Run Lint	2m 35s
Check Go Generate (flytepropeller) / Go Generate	2m 32s
Lint (flyteadmin) / Run Lint	3m 39s
Lint (flyteidl) / Run Lint	1m 59s
Lint (flyteplugins) / Run Lint	3m 26s
Lint (flytepropeller) / Run Lint	3m 29s
Lint (flytestdlib) / Run Lint	3m 5s
Unit Tests (datacatalog) / Run Unit Test	3m 20s
Unit Tests (flyteadmin) / Run Unit Test	4m 28s
Unit Tests (flytecopilot) / Run Unit Test	2m 41s
Unit Tests (flyteplugins) / Run Unit Test	4m 3s
Unit Tests (flytepropeller) / Run Unit Test	4m 16s
Unit Tests (flytestdlib) / Run Unit Test	4m 15s
Integration Test (flyteadmin) / Integration tests	5m 36s
	1h 22m 2s

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