Map<ReplicaKey, ReplicaState> observerStates(final long currentTimeMs) {
        clearInactiveObservers(currentTimeMs);
        return observerStates;
    }
Reset the checkQuorumTimer if we've received fetch/fetchSnapshot request from the majority of the voter

@param replicaKey the replica key of the voter
@param currentTimeMs the current timestamp in millisecond
raft/src/main/java/org/apache/kafka/raft/LeaderState.java