fix a dead lock on receiving message request approval

SessionMessagingKit/Sending & Receiving/MessageReceiver+Handling.swift

@@ -817,8 +817,10 @@ extension MessageReceiver {
         // Force a config sync to ensure all devices know the contact approval state if desired
         guard forceConfigSync else { return }
         
+        transaction.addCompletionQueue(Threading.jobQueue) {
             MessageSender.syncConfiguration(forceSyncNow: true).retainUntilComplete()
         }
+    }
     
     public static func handleMessageRequestResponse(_ message: MessageRequestResponse, using transaction: Any) {
         let userPublicKey = getUserHexEncodedPublicKey()