storage: only fail circuit breaker on RPC errors
storage: only fail circuit breaker on RPC errors

We were previously opening the Raft transport circuit breaker to a node
when a snapshot failed to apply (an application level error) which would
then cause all Raft traffic to the node to be dropped for 500ms-1s.

Fixes #9545

glycerine/cockroach,veteranlu/cockroach,maxlang/cockroach,vaibhavarora/cockroach,maxlang/cockroach,veteranlu/cockroach,petermattis/cockroach,cockroachdb/cockroach,paperstreet/cockroach,glycerine/cockroach,petermattis/cockroach,glycerine/cockroach,cockroachdb/cockroach,paperstreet/cockroach,maxlang/cockroach,maxlang/cockroach,veteranlu/cockroach,paperstreet/cockroach,glycerine/cockroach,petermattis/cockroach,veteranlu/cockroach,petermattis/cockroach,vaibhavarora/cockroach,cockroachdb/cockroach,veteranlu/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,maxlang/cockroach,vaibhavarora/cockroach,paperstreet/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,cockroachdb/cockroach,maxlang/cockroach,paperstreet/cockroach,cockroachdb/cockroach,glycerine/cockroach,veteranlu/cockroach,maxlang/cockroach,glycerine/cockroach,paperstreet/cockroach,paperstreet/cockroach,glycerine/cockroach,petermattis/cockroach,vaibhavarora/cockroach,vaibhavarora/cockroach,petermattis/cockroach,cockroachdb/cockroach,vaibhavarora/cockroach,petermattis/cockroach,vaibhavarora/cockroach,petermattis/cockroach,glycerine/cockroach,maxlang/cockroach,paperstreet/cockroach,veteranlu/cockroach