Fix queueStore stops working with concurrent PUT/DELETE requests (#8381)

- This PR fixes situation to avoid underflow, this is possible
  because of disconnected operations in replay/sendEvents
- Hold right locks if Del() operation is performed in Get()
- Remove panic in the code and use loggerOnce
- Remove Timer and instead use Ticker instead for proper ticks

pkg/event/target/nats.go

@@ -17,6 +17,7 @@
 package target
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"net/url"
@@ -233,7 +234,7 @@ func (target *NATSTarget) Close() (err error) {
 }
 
 // NewNATSTarget - creates new NATS target.
-func NewNATSTarget(id string, args NATSArgs, doneCh <-chan struct{}) (*NATSTarget, error) {
+func NewNATSTarget(id string, args NATSArgs, doneCh <-chan struct{}, loggerOnce func(ctx context.Context, err error, id interface{})) (*NATSTarget, error) {
 	var natsConn *nats.Conn
 	var stanConn stan.Conn
 
@@ -271,9 +272,9 @@ func NewNATSTarget(id string, args NATSArgs, doneCh <-chan struct{}) (*NATSTarge
 
 	if target.store != nil {
 		// Replays the events from the store.
-		eventKeyCh := replayEvents(target.store, doneCh)
+		eventKeyCh := replayEvents(target.store, doneCh, loggerOnce, target.ID())
 		// Start replaying events from the store.
-		go sendEvents(target, eventKeyCh, doneCh)
+		go sendEvents(target, eventKeyCh, doneCh, loggerOnce)
 	}
 
 	return target, nil