npm: bump postcss from 8.5.5 to 8.5.6 in the minor-updates group (#288)

Bumps the minor-updates group with 1 update: [postcss](https://github.com/postcss/postcss).


Updates `postcss` from 8.5.5 to 8.5.6
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.5...8.5.6)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: minor-updates
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

package-lock.json

@@ -13,7 +13,7 @@
   },
   "devDependencies": {
     "autoprefixer": "^10.4.21",
-    "postcss": "^8.5.5",
+    "postcss": "^8.5.6",
     "postcss-cli": "^11.0.1"
   }
 }