Upgrade: Bump postcss-loader from 7.3.3 to 7.3.4

Bumps [postcss-loader](https://github.com/webpack-contrib/postcss-loader) from 7.3.3 to 7.3.4.
- [Release notes](https://github.com/webpack-contrib/postcss-loader/releases)
- [Changelog](https://github.com/webpack-contrib/postcss-loader/blob/master/CHANGELOG.md)
- [Commits](webpack-contrib/postcss-loader@v7.3.3...v7.3.4)

---
updated-dependencies:
- dependency-name: postcss-loader
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -48,7 +48,7 @@
     "postcss-cli": "^10.1.0",
     "postcss-flexbugs-fixes": "^5.0.2",
     "postcss-import": "^15.1.0",
-    "postcss-loader": "^7.3.3",
+    "postcss-loader": "^7.3.4",
     "postcss-preset-env": "^9.3.0",
     "prismjs": "^1.29.0",
     "regenerator-runtime": "^0.14.0",