Update linting

.eslintrc.js

@@ -5,9 +5,9 @@ module.exports = {
     server: true,
   },
   root: true,
-  parser: 'babel-eslint',
+  parser: '@babel/eslint-parser',
   parserOptions: {
-    ecmaVersion: 2018,
+    ecmaVersion: 2020,
     sourceType: 'module',
     ecmaFeatures: {
       legacyDecorators: true,

addon/components/docs-header/search-results/index.js

@@ -1,3 +1,4 @@
+/* eslint-disable ember/require-computed-property-dependencies */
 import { inject as service } from '@ember/service';
 import Component from '@ember/component';
 import { action } from '@ember/object';

babel.config.js

@@ -0,0 +1,12 @@
+/* eslint-env node */
+
+module.exports = {
+  plugins: [
+    [
+      require('@babel/plugin-proposal-decorators').default,
+      {
+        legacy: true,
+      },
+    ],
+  ],
+};

package.json

@@ -103,6 +103,7 @@
   },
   "devDependencies": {
     "@babel/eslint-parser": "^7.16.0",
+    "@babel/plugin-proposal-decorators": "^7.16.0",
     "@ember/optional-features": "^2.0.0",
     "@ember/test-helpers": "^2.4.2",
     "@embroider/test-setup": "^0.47.2",

sandbox/.eslintrc.js

@@ -1,9 +1,10 @@
 module.exports = {
   root: true,
-  parser: 'babel-eslint',
+  parser: '@babel/eslint-parser',
   parserOptions: {
-    ecmaVersion: 2017,
-    sourceType: 'module'
+    ecmaVersion: 2020,
+    sourceType: 'module',
+    requireConfigFile: false
   },
   plugins: [
     'ember'