[System Test] Rebalance failure observed with indexer panic in longevity

ns_vbucket_mover:0:info:message(ns_1@172.23.97.74) - Bucket "default" rebalance appears to be swap rebalance

2021-02-14T13:38:51.554-08:00, ns_orchestrator:0:critical:message(ns_1@172.23.97.74) - Rebalance exited with reason {service_rebalance_failed,index,

                                 {agent_died,<30392.30806.0>,

                                     {lost_connection,shutdown}}}.

Rebalance Operation Id = e10cdb9eef30f4793dc9bb40e785d795

2021-02-14T13:38:51.569-08:00, ns_log:0:info:message(ns_1@172.23.96.243) - Service 'indexer' exited with status 2. Restarting. Messages:

github.com/couchbase/indexing/secondary/indexer.(*plasmaSlice).insertSecIndex(0xc01766cc00, 0xc019c1cca0, 0xd, 0x10, 0xc0080ad3a0, 0x12, 0x20, 0x7, 0x4c2400, 0xc00b798800, ...)

	/home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/plasma_slice.go:775 +0xb18

github.com/couchbase/indexing/secondary/indexer.(*plasmaSlice).insert(0xc01766cc00, 0xc019c1cca0, 0xd, 0x10, 0xc0080ad3a0, 0x12, 0x20, 0x7, 0x400, 0xc00b798800, ...)

	/home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/plasma_slice.go:733 +0x164

github.com/couchbase/indexing/secondary/indexer.(*plasmaSlice).handleCommandsWorker(0xc01766cc00, 0x7)

	/home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/plasma_slice.go:610 +0x58a

created by github.com/couchbase/indexing/secondary/indexer.(*plasmaSlice).initWriters

	/home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/plasma_slice.go:2969 +0x521

2021-02-14T13:39:24.214-08:00, indexing:0:info:message(ns_1@172.23.96.243) - Detected storage corruption for index default_rating, partition id 0. Starting cleanup.

2021-02-14T13:39:24.411-08:00, indexing:0:info:message(ns_1@172.23.96.243) - Cleanup done for index default_rating, partition id 0.