ref(project-cache): Revert project cache split and metric meta removal #16113

Job	Run time
Lint	3m 26s
Lint Rust Default Features	2m 10s
Test (macos-latest)	2m 33s
Test (windows-latest)	5m 59s
Test All Features (ubuntu-latest)	3m 33s
Setup build metadata	1s
Integration Tests	11m 22s
Test Python	1m 17s
Build Relay Binary (relay, x86_64-unknown-linux-gnu)	8m 7s
Build Docker Image (relay)	47s
Sentry-Relay Integration Tests	14m 30s
Publish Relay to DockerHub	0s
Upload build artifacts to gocd	0s
Publish Relay to GCR	0s
self-hosted-end-to-end	14m 5s
	1h 7m 50s

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