Fixed total_restart_test since we won't reassign nodes any more
Fixed total_restart_test since we won't reassign nodes any more

There's no need to catch the sender_removed exception now that the
subgroup allocation function won't reassign nodes to a different shard.

Derecho-Project/derecho-unified,Derecho-Project/derecho-unified,Derecho-Project/derecho-unified,Derecho-Project/derecho-unified,Derecho-Project/derecho-unified