Remove rules forbidding es6

.eslintrc.json

@@ -72,8 +72,7 @@
                 "balanced": true
             },
             "exceptions": ["*"]
-        }],
-        "es5/no-es6-methods": ["warn"]
+        }]
     },
     "env": {
         "browser": true
@@ -83,7 +82,6 @@
         "goog": true
     },
     "extends": [
-        "eslint:recommended",
-        "plugin:es5/no-es2015"
+        "eslint:recommended"
     ]
 }

core/utils/object.js

@@ -62,9 +62,7 @@ Blockly.utils.object.deepMerge = function(target, source) {
  */
 Blockly.utils.object.values = function(obj) {
   if (Object.values) {
-    /* eslint-disable es5/no-es6-methods */
     return Object.values(obj);
-    /* eslint-enable es5/no-es6-methods */
   }
   // Fallback for IE.
   return Object.keys(obj).map(function(e) {

package.json

@@ -69,7 +69,6 @@
     "clang-format": "^1.5.0",
     "concurrently": "^6.0.0",
     "eslint": "^7.6.0",
-    "eslint-plugin-es5": "^1.5.0",
     "google-closure-compiler": "^20210302.0.0",
     "google-closure-deps": "^20210202.0.0",
     "gulp": "^4.0.2",