Schedule indexes get stuck in schedule stage during rebalance out of assigned node

Rebalancing out of assigned node of an index during schedule stage make index stuck on reassigned node.

Steps to reproduce:-

1. Have 3 nodes cluster (index-kv-query, index, index) with 1B-1S-1C and 1M docs.
2. Create multiple indexes in parallel (say 10) with 1 replica num and preassigned deploy node. 

   CREATE INDEX idx_7 ON default:test_bucket.test_scope_1.test_collection_1(suffix) USING GSI WITH {'nodes': ['10.112.205.102:8091', '10.112.205.103:8091'], 'defer_build': True}

3. Rebalance out one of the assigned node before indexes moved out of schedule state. (Also observed similar behaviour if one of the assigned node is failed over)
4. Observer that all the indexes get reassigned to other available index node in cluster and comes out of schedule state.