Merge branch '6.4' into 7.0

* 6.4:
  [Scheduler] Fix code sample

Author: javiereguiluz

scheduler.rst

@@ -901,7 +901,7 @@ same task more than once::
                 ->with(
                     // ...
                 )
-                ->lock($this->lockFactory->createLock('my-lock')
+                ->lock($this->lockFactory->createLock('my-lock'));
         }
     }