[BP to 7.0.4] - [System test upgrade] - Index build stuck during rebalance due to large number of pending items

"name": "idx4_8C6JX",

   "bucket": "bucket6",

   "scope": "scope_0",

   "collection": "coll_2",

   "secExprs": [

    "`price`",

    "`city`",

    "`name`"

   ],

   "indexType": "plasma",

   "status": "Moving",

   "definition": "CREATE INDEX `idx4_8C6JX` ON `bucket6`.`scope_0`.`coll_2`(`price`,`city`,`name`) PARTITION BY hash((meta().`id`)) WITH { \"nodes\":[ \"172.23.120.77:18091\",\"172.23.123.26:18091\",\"172.23.123.33:18091\",\"172.23.97.105:18091\",\"172.23.97.148:18091\",\"172.23.97.149:18091\" ], \"num_replica\":2, \"num_partition\":5 }",

   "hosts": [

    "172.23.120.77:18091",

    "172.23.123.33:18091",

    "172.23.97.105:18091",

    "172.23.97.148:18091"

   ],

   "completion": 100,

   "progress": 100,

   "scheduled": false,

2022-02-24T01:23:37.682-08:00 [Info] Rebalancer::waitForIndexBuild Index: bucket6:scope_0:coll_2:idx4_8C6JX State: INDEX_STATE_ACTIVE Pending: 2.7228046e+07 EstTime: 79 Partitions: [5] Destination: 127.0.0.1:9102

2022-02-24T01:23:40.698-08:00 [Info] Rebalancer::waitForIndexBuild Index: bucket6:scope_0:coll_2:idx4_8C6JX State: INDEX_STATE_ACTIVE Pending: 2.7228046e+07 EstTime: 79 Partitions: [5] Destination: 127.0.0.1:9102