Update README.md

Author: sc0Vu

README.md

@@ -30,7 +30,6 @@ Usage in Vue 3:
 ```js
 const app = Vue.createApp(...)
 app.use(VueAxios, axios)
-app.mount('#app')
 ```
 
 ### Script:

src/index.js

@@ -45,6 +45,7 @@ function plugin(app, axios) {
   }
 
   app.axios = axios;
+  app.$http = axios;
 }
 
 if (typeof exports == "object") {