SplitRecoveryIT failing due to StackOverflowError

[dlmarion]

The TabletServer ends up dying because the AssignmentHandler keeps invoking a new AssignmentHandler (line 129) resulting in a StackOverflowError. I wonder if this condition should be added to the TabletManagementIterator and handled in the TabletGroupWatcher before the extent is assigned for hosting?

[dlmarion]

This was resolved by #4136