[infra] Remove transform-runtime from next/babel (#46552)

Author: Janpot

docs/babel.config.js

@@ -1,24 +1,9 @@
-const fse = require('fs-extra');
-
-const { version: transformRuntimeVersion } = fse.readJSONSync(
-  require.resolve('@babel/runtime-corejs2/package.json'),
-);
-
 module.exports = {
   assumptions: {
     noDocumentAll: true,
     setSpreadProperties: true,
   },
-  presets: [
-    // backport of https://github.com/vercel/next.js/pull/9511
-    [
-      'next/babel',
-      {
-        'preset-react': { runtime: 'automatic' },
-        'transform-runtime': { corejs: 2, version: transformRuntimeVersion },
-      },
-    ],
-  ],
+  presets: ['next/babel'],
   plugins: ['babel-plugin-optimize-clsx'],
   ignore: [/@babel[\\|/]runtime/], // Fix a Windows issue.
   env: {

docs/package.json

@@ -19,7 +19,6 @@
   "dependencies": {
     "@babel/core": "^7.28.0",
     "@babel/runtime": "^7.27.6",
-    "@babel/runtime-corejs2": "^7.27.6",
     "@docsearch/react": "^3.9.0",
     "@emotion/cache": "^11.14.0",
     "@emotion/react": "^11.14.0",
@@ -64,7 +63,6 @@
     "clean-css": "^5.3.3",
     "clipboard-copy": "^4.0.1",
     "clsx": "^2.1.1",
-    "core-js": "^2.6.11",
     "cross-env": "^7.0.3",
     "css-mediaquery": "^0.1.2",
     "dayjs": "^1.11.13",