Mark empty functions as intentionally empty

Author: wojtekmaj

__mocks__/update-input-width.js

@@ -1 +1,3 @@
-module.exports = () => {};
+module.exports = () => {
+  // Intentionally empty
+};

src/DateTimeInput/NativeInput.spec.jsx

@@ -5,7 +5,9 @@ import NativeInput from './NativeInput';
 
 describe('NativeInput', () => {
   const defaultProps = {
-    onChange: () => {},
+    onChange: () => {
+      // Intentionally empty
+    },
     valueType: 'second',
   };