fix: upgrade postcss from 8.4.23 to 8.4.24 (#145)

Snyk has created this PR to upgrade postcss from 8.4.23 to 8.4.24.

See this package in npm:
https://www.npmjs.com/package/postcss

See this project in Snyk:
https://app.snyk.io/org/plan-x/project/43ecce79-408c-4464-831c-06da1d999308?utm_source=github&utm_medium=referral&page=upgrade-pr

Co-authored-by: snyk-bot <snyk-bot@snyk.io>

package.json

@@ -67,7 +67,7 @@
     "install": "^0.13.0",
     "jest": "^26.0.0",
     "minimist": "^1.2.0",
-    "postcss": "^8.0.0",
+    "postcss": "^8.4.24",
     "postcss-assets": "^6.0.0",
     "postcss-cli": "^8.0.0",
     "postcss-less": "^6.0.0",