Bump postcss in /docs in the npm_and_yarn group across 1 directory

Bumps the npm_and_yarn group with 1 update in the /docs directory: [postcss](https://github.com/postcss/postcss).


Updates `postcss` from 8.5.6 to 8.5.12
- [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/8.5.6...8.5.12)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.12
  dependency-type: indirect
  dependency-group: npm_and_yarn
...

Signed-off-by: dependabot[bot] <support@github.com>

docs/package-lock.json

@@ -2040,9 +2040,9 @@
             "license": "ISC"
         },
         "node_modules/postcss": {
-            "version": "8.5.6",
-            "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.6.tgz",
-            "integrity": "sha512-3Ybi1tAuwAP9s0r1UQ2J4n5Y0G05bJkpUIO0/bI9MhwmD70S5aTWbXGBwxHrelT+XM1k6dM0pk+SwNkpTRN7Pg==",
+            "version": "8.5.12",
+            "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.12.tgz",
+            "integrity": "sha512-W62t/Se6rA0Az3DfCL0AqJwXuKwBeYg6nOaIgzP+xZ7N5BFCI7DYi1qs6ygUYT6rvfi6t9k65UMLJC+PHZpDAA==",
             "dev": true,
             "funding": [
                 {