Bump postcss from 8.4.12 to 8.4.21

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.12 to 8.4.21.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.12...8.4.21)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package.json

@@ -38,7 +38,7 @@
     "@fullhuman/postcss-purgecss": "^4.1.3",
     "bootilities": "^0.5.0",
     "jest": "^27.5.1",
-    "postcss": "^8.4.12",
+    "postcss": "^8.4.21",
     "prettier": "^2.4.1",
     "sass": "^1.43.4",
     "ts-jest": "^27.1.4",

yarn.lock

@@ -3231,10 +3231,10 @@ mustache@^4.2.0:
   resolved "https://registry.yarnpkg.com/mustache/-/mustache-4.2.0.tgz#e5892324d60a12ec9c2a73359edca52972bf6f64"
   integrity sha512-71ippSywq5Yb7/tVYyGbkBggbU8H3u5Rz56fH60jGFgr8uHwxs+aSKeqmluIVzM0m0kB7xQjKS6qPfd0b2ZoqQ==
 
-nanoid@^3.3.1:
-  version "3.3.1"
-  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.3.1.tgz#6347a18cac88af88f58af0b3594b723d5e99bb35"
-  integrity sha512-n6Vs/3KGyxPQd6uO0eH4Bv0ojGSUvuLlIHtC3Y0kEO23YRge8H9x1GCzLn28YX0H66pMkxuaeESFq4tKISKwdw==
+nanoid@^3.3.4:
+  version "3.3.4"
+  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.3.4.tgz#730b67e3cd09e2deacf03c027c81c9d9dbc5e8ab"
+  integrity sha512-MqBkQh/OHTS2egovRtLk45wEyNXwF+cokD+1YPf9u5VfJiRdAiRwB2froX5Co9Rh20xs4siNPm8naNotSD6RBw==
 
 natural-compare@^1.4.0:
   version "1.4.0"
@@ -3529,12 +3529,12 @@ postcss-value-parser@^4.0.0, postcss-value-parser@^4.2.0:
   resolved "https://registry.yarnpkg.com/postcss-value-parser/-/postcss-value-parser-4.2.0.tgz#723c09920836ba6d3e5af019f92bc0971c02e514"
   integrity sha512-1NNCs6uurfkVbeXG4S8JFT9t19m45ICnif8zWLd5oPSZ50QnwMfK+H3jv408d4jw/7Bttv5axS5IiHoLaVNHeQ==
 
-postcss@^8.3.5, postcss@^8.4.12, postcss@^8.4.6:
-  version "8.4.12"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.12.tgz#1e7de78733b28970fa4743f7da6f3763648b1905"
-  integrity sha512-lg6eITwYe9v6Hr5CncVbK70SoioNQIq81nsaG86ev5hAidQvmOeETBqs7jm43K2F5/Ley3ytDtriImV6TpNiSg==
+postcss@^8.3.5, postcss@^8.4.12, postcss@^8.4.21, postcss@^8.4.6:
+  version "8.4.21"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.21.tgz#c639b719a57efc3187b13a1d765675485f4134f4"
+  integrity sha512-tP7u/Sn/dVxK2NnruI4H9BG+x+Wxz6oeZ1cJ8P6G/PZY0IKk4k/63TDsQf2kQq3+qoJeLm2kIBUNlZe3zgb4Zg==
   dependencies:
-    nanoid "^3.3.1"
+    nanoid "^3.3.4"
     picocolors "^1.0.0"
     source-map-js "^1.0.2"