Fix crash

SignalServiceKit/src/Loki/Protocol/Sync Messages/SyncMessagesProtocol.swift

@@ -175,16 +175,13 @@ public final class SyncMessagesProtocol : NSObject {
                 let autoGeneratedFRMessage = MultiDeviceProtocol.getAutoGeneratedMultiDeviceFRMessage(for: hexEncodedPublicKey, in: transaction)
                 thread.isForceHidden = true
                 thread.save(with: transaction)
+                // This takes into account multi device
                 messageSender.send(autoGeneratedFRMessage, success: {
-                    storage.dbReadWriteConnection.readWrite { transaction in
-                        autoGeneratedFRMessage.remove()
-                        thread.isForceHidden = false
-                    }
+                    autoGeneratedFRMessage.remove(with: transaction)
+                    thread.isForceHidden = false
                 }, failure: { error in
-                    storage.dbReadWriteConnection.readWrite { transaction in
-                        autoGeneratedFRMessage.remove()
-                        thread.isForceHidden = false
-                    }
+                    autoGeneratedFRMessage.remove(with: transaction)
+                    thread.isForceHidden = false
                 })
             case .requestReceived:
                 thread.saveFriendRequestStatus(.friends, with: transaction)