Unpin google.golang.org/grpc from go.mod

[perdasilva]

Description

Version 1.64.0 of google.golang.org/grpc changes the way the CatalogSource connection state behaves.
previously it would automatically reach READY - but with the new library, it seems to stay on IDLE unless there is data going down the pipe this is breaking many CatalogSource related e2e-tests and also affecting the way CatalogSource metrics work (since it introduces a more frequent transitions between IDLE and READY the READY/NOTREADY gauges go a bit loopy)

Possible Fixes

Either:

• A CatalogSourceState of "READY" would now mean gRPC connection state in {READY, IDLE} (unclear whether this makes sense)
• Or, introduce a periodic health-check (but, Pods already have health-checks!)
• Or, switch to looking at the pod for CatalogSourceState (i.e. READY == Pod is READY, TRANSIENT_ERROR == Pod not ready) (But, what about the address only CatalogSources...?)