Add delay and count parameters to $interval call

Angular ~1.5 expects there to be a delay param. In ngMock, there is no default value for the delay, so you effectively have `time + undefined`, which yields a string.

src/infinite-scroll.js

@@ -261,7 +261,7 @@ angular.module(MODULE_NAME, [])
         return $interval.cancel(checkInterval);
       }
 
-      checkInterval = $interval(intervalCheck);
+      checkInterval = $interval(intervalCheck, 0, 1);
       return checkInterval;
     },
   }),