update buidler version

Author: EryouHao

package.json

@@ -108,7 +108,7 @@
     "postcss-import": "^12.0.1",
     "tailwindcss": "^1.1.4",
     "typescript": "^3.0.0",
-    "vue-cli-plugin-electron-builder": "^2.0.0",
+    "vue-cli-plugin-electron-builder": "2.0.0-beta.2",
     "vue-template-compiler": "^2.6.10"
   },
   "main": "background.js",