Update ESLint to v9.4.0 and regenerate package-lock.json (twbs#2012)

Author: XhmikosR

.eslintignore

@@ -0,0 +1,60 @@
+import js from '@eslint/js'
+import globals from 'globals'
+
+/** @type {import('eslint').Linter.FlatConfig[]} */
+export default [
+  // global ignores
+  {
+    ignores: [
+      '**/*.min.js',
+      '**/dist/**',
+      '**/vendor/**',
+      '_site/**',
+      'node_modules/**',
+      'resources/**',
+      '**/.fantasticonrc.js'
+    ],
+  },
+  {
+    languageOptions: {
+      ecmaVersion: 2020,
+      sourceType: 'module',
+      globals: {
+        ...globals.nodeBuiltin
+      }
+    },
+    linterOptions: {
+      reportUnusedDisableDirectives: 'error'
+    }
+  },
+  js.configs.recommended,
+  {
+    files: [
+      '**/*.js',
+      '**/*.mjs'
+    ],
+    rules: {
+      'no-return-await': 'error',
+      'object-curly-spacing': [
+        'error',
+        'always'
+      ],
+      'prefer-template': 'error',
+      semi: [
+        'error',
+        'never'
+      ],
+      strict: 'error'
+    }
+  },
+  {
+    files: [
+      'docs/assets/js/**'
+    ],
+    languageOptions: {
+      globals: {
+        ...globals.browser
+      }
+    }
+  }
+]