dep: bump @tailwindcss/postcss from 4.1.0 to 4.1.5

Bumps [@tailwindcss/postcss](https://github.com/tailwindlabs/tailwindcss/tree/HEAD/packages/@tailwindcss-postcss) from 4.1.0 to 4.1.5.
- [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/v4.1.5/packages/@tailwindcss-postcss)

---
updated-dependencies:
- dependency-name: "@tailwindcss/postcss"
  dependency-version: 4.1.5
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

package-lock.json

@@ -52,7 +52,7 @@
   ],
   "dependencies": {
     "@fortawesome/fontawesome-free": "^6.7.2",
-    "@tailwindcss/postcss": "^4.1.0",
+    "@tailwindcss/postcss": "^4.1.5",
     "autoprefixer": "^10.4.21",
     "github-markdown-css": "^5.8.1",
     "gulp": "^5.0.0",