Match function call with function signature

Looks like its calling a function that doesn't take a parameter with a parameter.

Commit that added this:
3dbc951

src/Elasticsearch/Endpoints/Index.php

@@ -76,7 +76,7 @@ protected function getURI()
         }
 
         if ($this->createIfAbsent === true) {
-            $uri .= $this->addCreateFlag($uri);
+            $uri .= $this->addCreateFlag();
         }
 
         return $uri;
@@ -139,4 +139,4 @@ private function addCreateFlag()
         }
 
     }
-}
+}