kvserver: avoid starting async raft worker on error

Epic: None

Fixes: None

Release note: None

Author: cthumuluru-crdb

pkg/kv/kvserver/scheduler.go

@@ -324,6 +324,7 @@ func (s *raftScheduler) Start(stopper *stop.Stopper) {
 				})
 			if err != nil {
 				s.done.Done()
+				continue
 			}
 			go f(ctx, hdl)
 		}