Bump postcss from 8.4.39 to 8.4.40

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.39 to 8.4.40.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.39...8.4.40)

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

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

package.json

@@ -26,7 +26,7 @@
     "autoprefixer": "^10.4.7",
     "core-js": "^3.27.2",
     "mobx": "^6.13.1",
-    "postcss": "^8.4.39",
+    "postcss": "^8.4.40",
     "react-github-btn": "^1.3.0",
     "react-icons": "^5.2.1",
     "styled-components": "^6.1.12",