refactor: drop bluebird

Author: davidyuk

babel.config.js

@@ -3,10 +3,7 @@ module.exports = {
     '@vue/cli-plugin-babel/preset',
   ],
   plugins: [
-    ['@babel/plugin-transform-async-to-generator', {
-      module: 'bluebird',
-      method: 'coroutine',
-    }],
-    ['@babel/plugin-syntax-import-attributes'],
+    '@babel/plugin-syntax-import-attributes',
+    '@babel/plugin-transform-private-methods',
   ],
 };