Indexer is trying to build queued indexes for a deleted database.

1. Create 19 databases to avoid kv/gsi auto-scaling due to num_tenants.
2. Create 10 collections(VolumeCollection0, VolumeCollection1....VolumeCollection0) in each database
3. Create 100 indexes on each database i.e. 10 on each collection. This results in total 1900 indexes.
4. Build 10 indexes per database at a time. Example:

   Bucket0:VolumeCollection0 - 10 indexes under build

   Bucket1:VolumeCollection0 - 10 indexes under build

   Bucket2:VolumeCollection0 - 10 indexes under build

   .

   .

   .

   Bucket19:VolumeCollection0 - 10 indexes under build

5. Observe that index build is getting started and aborted immediately. Which is reported in MB-55276 and discussed further in MB-55019
6. Delete all the databases at this state and observe that indexer is trying to build the queued indexes for deleted databases which leads to more issues like rebalance failures

   Rebalance exited with reason {service_rebalance_failed,index,

   {worker_died,

   {'EXIT',<0.11246.77>,

   {task_failed,rebalance,

   {service_error,

   <<"[Bucket does not exist or temporarily unavailable for creating new index. Please retry the operation at a later time.] Bucket volumetestbucket-5-cn0uqk does not exist or temporarily unavailable for creating new index. Please retry the operation at a later time.">>}}}}}.

   Rebalance Operation Id = 1f2fad995e51bc229f70a18dfefe75aa

   followed by:

   Service 'index' exited with status 2. Restarting. Messages:

   github.com/couchbase/indexing/secondary/indexer.(*indexer).handleStorageRollbackDone(0x400007f400, {0x1a9a7c8?, 0x403c565c40?})

   /home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/indexer.go:4102 +0x4a8

   github.com/couchbase/indexing/secondary/indexer.(*indexer).handleWorkerMsgs(0x400007f400, {0x1a9a7c8, 0x403c565c40})

   /home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/indexer.go:1540 +0x41c

   github.com/couchbase/indexing/secondary/indexer.(*indexer).run(0x400007f400)

   /home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/indexer.go:1130 +0x274

   github.com/couchbase/indexing/secondary/indexer.NewIndexer(0x27fd470?)

   /home/couchbase/jenkins/workspace/couchbase-server-unix/goproj/src/github.com/couchbase/indexing/secondary/indexer/indexer.go:556 +0x2024

   main.main()

   goproj/src/github.com/couchbase/indexing/secondary/cmd/indexer/main.go:206 +0xf90

cc: Deepkaran Salooja