chore(deps-dev): 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:development
  update-type: version-update:semver-patch
...

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

package.json

@@ -43,7 +43,7 @@
 		"eslint": "^7.32.0",
 		"lint-staged": "^15.2.7",
 		"newspack-scripts": "^5.5.1",
-		"postcss": "^8.4.39",
+		"postcss": "^8.4.40",
 		"postcss-scss": "^4.0.9",
 		"prettier": "npm:wp-prettier@^2.6.2-beta-1",
 		"regenerator-runtime": "^0.14.1",