Merge pull request #834 from moo-mou/patch-1

Fix typo

Author: mattpodwysocki

doc/api/core/operators/forkjoinproto.md

@@ -30,7 +30,7 @@ var subscription = source.subscribe(
         console.log('Completed');
     });
 
-// => Next: 44
+// => Next: 45
 // => Completed
 ```