Analytics: Rebalance stuck and fails while rebalancing in multiple NC nodes by first adding them and then rebalance.

Freshly install the server on 4 nodes:
1. In a cluster having 1 KV node and default bucket with 20k docs.
2. Add cbas node(CC) to the cluster and rebalance in. Setup cbas. All well till here.
3. Add 2 NC nodes and rebalance then in together. Observe that rebalance stuck at 8.33%.
4. Stop rebalance and remove all cbas nodes and repeat the process from step 1 to 3 and observe that this time rebalance is successful.