dep: bump @tailwindcss/postcss from 4.1.17 to 4.1.18 (#1370)

Bumps [@tailwindcss/postcss](https://github.com/tailwindlabs/tailwindcss/tree/HEAD/packages/@tailwindcss-postcss) from 4.1.17 to 4.1.18.
- [Release notes](https://github.com/tailwindlabs/tailwindcss/releases)
- [Changelog](https://github.com/tailwindlabs/tailwindcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/tailwindlabs/tailwindcss/commits/v4.1.18/packages/@tailwindcss-postcss)

Change-Id: Ic032ebccb0ce120d8839f3ed882ab4b6cfb1a8b9

---
updated-dependencies:
- dependency-name: "@tailwindcss/postcss"
  dependency-version: 4.1.18
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

package-lock.json

@@ -52,7 +52,7 @@
   ],
   "dependencies": {
     "@fortawesome/fontawesome-free": "^7.1.0",
-    "@tailwindcss/postcss": "^4.1.17",
+    "@tailwindcss/postcss": "^4.1.18",
     "autoprefixer": "^10.4.22",
     "github-markdown-css": "^5.8.1",
     "gulp": "^5.0.1",