We need to start responding to hello requests with ok:0 for Primary node when it fails to step down or replica set is only 1 node when forceShutdown is set to true here
same as we do for quiesce mode for secondaries here.

As Shutdown code assumes that primaries will always be able to step-down here so it will be a secondary and will be able to enter quiesce mode eventually but that might not be the case as primary can fail to stepDown due to multiple reasons for example not able to find suitable secondary to step_up

1. secondaries have been shutdown first
2. Replica Set can be formed from only one node.