Change metadata badges style.

Author: hiramhuang

README.md

@@ -1,7 +1,7 @@
 # WP Shortcode Advertising
-[![Total Downloads](https://img.shields.io/wordpress/plugin/dt/wp-shortcode-advertising.svg)](http://wordpress.org/plugins/wp-shortcode-advertising/)
-[![Plugin Version](https://img.shields.io/wordpress/plugin/v/wp-shortcode-advertising.svg)](https://wordpress.org/plugins/wp-shortcode-advertising/)
-[![License](https://img.shields.io/packagist/l/rilwis/wp-shortcode-advertising.svg)](https://wordpress.org/plugins/wp-shortcode-advertising/)
+[![Total Downloads](https://img.shields.io/wordpress/plugin/dt/wp-shortcode-advertising.svg?style=flat-square)](http://wordpress.org/plugins/wp-shortcode-advertising/)
+[![Plugin Version](https://img.shields.io/wordpress/plugin/v/wp-shortcode-advertising.svg?style=flat-square)](https://wordpress.org/plugins/wp-shortcode-advertising/)
+[![License](https://img.shields.io/packagist/l/rilwis/wp-shortcode-advertising.svg?style=flat-square)](https://wordpress.org/plugins/wp-shortcode-advertising/)
 
 📲 A plugin that allow you to insert advertisement via shortcode.