chore: add one rule to the .prettierrc.js (semi: true), remove unnecessary comments from the index.js

.prettierrc.js

@@ -2,4 +2,5 @@ module.exports = {
   singleQuote: true,
   trailingComma: 'all',
   arrowParens: 'avoid',
+  semi: true,
 };

index.js

@@ -1,7 +1,3 @@
-/**
- * @format
- */
-
 import { AppRegistry } from 'react-native';
 import App from './src/screens/App';
 import { name as appName } from './app.json';