Bump @babel/core from 7.20.12 to 7.21.0

Bumps [@babel/core](https://github.com/babel/babel/tree/HEAD/packages/babel-core) from 7.20.12 to 7.21.0.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/commits/v7.21.0/packages/babel-core)

---
updated-dependencies:
- dependency-name: "@babel/core"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -8,7 +8,7 @@
         "normalize.css": "^8.0.1"
     },
     "devDependencies": {
-        "@babel/core": "^7.20.12",
+        "@babel/core": "^7.21.0",
         "@babel/preset-env": "^7.20.2",
         "autoprefixer": "^10.4.13",
         "babel-loader": "^9.1.2",