feat: update to eslint-plugin-vue >= 6.1.2 and set ecmaVersion to 2020

Author: haoqunjiang

index.js

@@ -1,8 +1,5 @@
 module.exports = {
   extends: [
     require.resolve('eslint-config-standard')
-  ],
-  parserOptions: {
-    ecmaVersion: 2019
-  }
+  ]
 }

package.json

@@ -28,6 +28,7 @@
     "eslint-plugin-import": ">= 2.18.0",
     "eslint-plugin-node": ">= 9.1.0",
     "eslint-plugin-promise": ">= 4.2.1",
-    "eslint-plugin-standard": ">= 4.0.0"
+    "eslint-plugin-standard": ">= 4.0.0",
+    "eslint-plugin-vue": ">= 6.1.2"
   }
 }