Bump postcss from 8.4.17 to 8.4.18

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.17 to 8.4.18.
- [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/8.4.17...8.4.18)

---
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

@@ -50,7 +50,7 @@
     "lato-font": "^3.0.0",
     "mini-css-extract-plugin": "^2.6.1",
     "node-sass": "^7.0.3",
-    "postcss": "^8.4.17",
+    "postcss": "^8.4.18",
     "postcss-loader": "^7.0.1",
     "postcss-scss": "^4.0.5",
     "sass": "^1.55.0",

yarn.lock

@@ -4622,10 +4622,10 @@ postcss-value-parser@^4.1.0, 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@^8.4.17, postcss@^8.4.7:
-  version "8.4.17"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.17.tgz#f87863ec7cd353f81f7ab2dec5d67d861bbb1be5"
-  integrity sha512-UNxNOLQydcOFi41yHNMcKRZ39NeXlr8AxGuZJsdub8vIb12fHzcq37DTU/QtbI6WLxNg2gF9Z+8qtRwTj1UI1Q==
+postcss@^8.4.17, postcss@^8.4.18, postcss@^8.4.7:
+  version "8.4.18"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.18.tgz#6d50046ea7d3d66a85e0e782074e7203bc7fbca2"
+  integrity sha512-Wi8mWhncLJm11GATDaQKobXSNEYGUHeQLiQqDFG1qQ5UTDPTEvKw0Xt5NsTpktGTwLps3ByrWsBrG0rB8YQ9oA==
   dependencies:
     nanoid "^3.3.4"
     picocolors "^1.0.0"