We have to create a new FSM testing for testing that no critical section is help indefinitely. In particular, an initial setup could be to: 1) several threads perform reads and writes (these will have a maxTimeMS of 2s set), 2) one thread performs DDLs which can race with replica set write block, 3) one thread randomly enabling/disabling replica set write block for a time window of 5 seconds. We expect that the write operations could fail with ReplicaSetWriteBlock reason, while they should never fail due to the 
MaxTimeMSExpired error.