chore(deps-dev): bump postcss from 8.3.5 to 8.3.6

Bumps [postcss](https://github.com/postcss/postcss) from 8.3.5 to 8.3.6.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.3.5...8.3.6)

---
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

@@ -54,7 +54,7 @@
     "autoprefixer": "^10.3.1",
     "babel-preset-react-app": "^10.0.0",
     "cypress": "^8.0.0",
-    "postcss": "^8.3.5",
+    "postcss": "^8.3.6",
     "postcss-cli": "^8.3.1",
     "postcss-nested": "^5.0.5",
     "prettier": "2.3.2",