chore: add version badge for plugins [skip ci]

Author: yyx990803

packages/plugin-legacy/README.md

@@ -1,4 +1,4 @@
-# @vitejs/plugin-legacy
+# @vitejs/plugin-legacy [![npm](https://img.shields.io/npm/v/@vitejs/plugin-legacy.svg)](https://npmjs.com/package/@vitejs/plugin-legacy)
 
 **Note: this plugin requires `vite@^2.0.0-beta.12`**.
 
@@ -21,10 +21,7 @@ import legacy from '@vitejs/plugin-legacy'
 export default {
   plugins: [
     legacy({
-      targets: [
-        'defaults',
-        'not IE 11'
-      ]
+      targets: ['defaults', 'not IE 11']
     })
   ]
 }
@@ -115,14 +112,8 @@ import legacy from '@vitejs/plugin-legacy'
 export default {
   plugins: [
     legacy({
-      polyfills: [
-        'es.promise.finally',
-        'es/map',
-        'es/set'
-      ],
-      modernPolyfills: [
-        'es.promise.finally'
-      ]
+      polyfills: ['es.promise.finally', 'es/map', 'es/set'],
+      modernPolyfills: ['es.promise.finally']
     })
   ]
 }

packages/plugin-react-refresh/README.md

@@ -1,4 +1,4 @@
-# @vitejs/plugin-react-refresh
+# @vitejs/plugin-react-refresh [![npm](https://img.shields.io/npm/v/@vitejs/plugin-react-refresh.svg)](https://npmjs.com/package/@vitejs/plugin-react-refresh)
 
 Provides [React Refresh](https://www.npmjs.com/package/react-refresh) support for Vite.
 

packages/plugin-vue-jsx/README.md

@@ -1,4 +1,4 @@
-# @vitejs/plugin-vue-jsx
+# @vitejs/plugin-vue-jsx [![npm](https://img.shields.io/npm/v/@vitejs/plugin-vue-jsx.svg)](https://npmjs.com/package/@vitejs/plugin-vue-jsx)
 
 Provides Vue 3 JSX & TSX support with HMR.
 

packages/plugin-vue/README.md

@@ -1,4 +1,4 @@
-# @vitejs/plugin-vue
+# @vitejs/plugin-vue [![npm](https://img.shields.io/npm/v/@vitejs/plugin-vue.svg)](https://npmjs.com/package/@vitejs/plugin-vue)
 
 Note: requires `@vue/compiler-sfc` as peer dependency. This is largely a port of `rollup-plugin-vue` with some vite-specific tweaks.