ci: improve size script

packages/size-check/package.json

@@ -2,10 +2,10 @@
   "name": "@vue/size-check",
   "version": "3.2.16",
   "private": true,
-  "buildOptions": {
-    "name": "Vue",
-    "formats": [
-      "global"
-    ]
+  "scripts": {
+    "build": "vite build"
+  },
+  "devDependencies": {
+    "vite": "^2.5.10"
   }
 }

packages/size-check/src/index.ts

@@ -1,4 +1,4 @@
-import { h, createApp } from '@vue/runtime-dom'
+import { h, createApp } from 'vue'
 
 // The bare minimum code required for rendering something to the screen
 createApp({

packages/size-check/vite.config.js

@@ -0,0 +1,10 @@
+export default {
+  build: {
+    rollupOptions: {
+      input: ['src/index.ts'],
+      output: {
+        entryFileNames: `[name].js`
+      }
+    }
+  }
+}