Bump postcss from 8.3.5 to 8.3.6 (#3527)

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
...

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

package.json

@@ -349,7 +349,7 @@
     "node-sass": "^4.14.1",
     "nodemon": "^2.0.12",
     "patch-package": "^6.2.2",
-    "postcss": "^8.2.14",
+    "postcss": "^8.3.6",
     "postcss-loader": "4.0.3",
     "postinstall-postinstall": "^2.1.0",
     "progress-bar-webpack-plugin": "^2.1.0",