Update README, CONTRIBUTING, DEVELOPER to the new standard #7789

Job	Run time
Typecheck and Lint Core	2m 46s
Build Core and publish docker image	5m 50s
Test Core	4m 7s
Build gateways (playout-gateway)	1m 23s
Lint Package (blueprints-integration)	57s
Build gateways (mos-gateway)	1m 22s
Lint Package (server-core-integration)	59s
Lint Package (playout-gateway)	1m 3s
Lint Package (mos-gateway)	1m 3s
Lint Package (corelib)	1m 11s
Test Package (blueprints-integration, 14.x)	1m 4s
Lint Package (shared-lib)	56s
Test Package (blueprints-integration, 16.x)	1m 1s
Lint Package (job-worker)	1m 28s
Test Package (server-core-integration, 14.x)	1m 18s
Test Package (server-core-integration, 16.x)	1m 13s
Test Package (shared-lib, 14.x)	1m 4s
Test Package (shared-lib, 16.x)	1m 4s
Check for multiple library versions	1m 19s
Test Package (14.x, corelib, true)	1m 28s
Test Package (14.x, job-worker, true)	2m 16s
Publish Docs	2m 20s
Release Lib	0s
	37m 12s

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