docs(README.md): updating badges to include user card component sample

Author: willmendesneto

README.md

@@ -2,6 +2,7 @@
 
 [![npm downloads](https://img.shields.io/npm/dm/ngx-skeleton-loader.svg)](https://npmjs.org/ngx-skeleton-loader)
 [![npm](https://img.shields.io/badge/stackblitz-online-orange.svg)](https://stackblitz.com/edit/ngx-skeleton-loader-sample)
+[![npm](https://img.shields.io/badge/stackblitz-online-orange.svg)](https://stackblitz.com/edit/ngx-skeleton-loader-user-card-component-sample)
 
 [![NPM](https://nodei.co/npm/ngx-skeleton-loader.png?downloads=true&downloadRank=true&stars=true)](https://npmjs.org/ngx-skeleton-loader)
 [![NPM](https://nodei.co/npm-dl/ngx-skeleton-loader.png?height=3&months=3)](https://npmjs.org/ngx-skeleton-loader)