Update clang-format version to 6.0

* coding convention fixed following the new clang-format

Signed-off-by: HyukWoo Park <hyukwoo.park@samsung.com>

src/runtime/ScriptFunctionObject.cpp

@@ -167,4 +167,4 @@ void ScriptFunctionObject::generateArgumentsObject(ExecutionState& state, size_t
         }
     }
 }
-}
+} // namespace Escargot