Bump postcss from 8.4.17 to 8.4.31 in /website (#183)

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.17 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.17...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: indirect
...

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

Author: dependabot[bot]

website/package-lock.json

@@ -4741,9 +4741,9 @@ multicast-dns@^7.2.5:
     dns-packet "^5.2.2"
     thunky "^1.0.2"
 
-nanoid@^3.3.4:
-  version "3.3.4"
-  resolved "https://registry.npmjs.org/nanoid/-/nanoid-3.3.4.tgz"
+nanoid@^3.3.6:
+  version "3.3.6"
+  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.3.6.tgz#443380c856d6e9f9824267d960b4236ad583ea4c"
 
 [email protected]:
   version "0.6.3"
@@ -5305,10 +5305,10 @@ postcss-zindex@^5.1.0:
   resolved "https://registry.npmjs.org/postcss-zindex/-/postcss-zindex-5.1.0.tgz"
 
 postcss@^8.3.11, postcss@^8.4.14, postcss@^8.4.17, postcss@^8.4.7:
-  version "8.4.17"
-  resolved "https://registry.npmjs.org/postcss/-/postcss-8.4.17.tgz"
+  version "8.4.31"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.31.tgz#92b451050a9f914da6755af352bdc0192508656d"
   dependencies:
-    nanoid "^3.3.4"
+    nanoid "^3.3.6"
     picocolors "^1.0.0"
     source-map-js "^1.0.2"