Bump postcss and next (#89)

Bumps [postcss](https://github.com/postcss/postcss) to 8.4.31 and updates ancestor dependency [next](https://github.com/vercel/next.js). These dependencies need to be updated together.


Updates `postcss` from 8.4.27 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@8.4.27...8.4.31)

Updates `next` from 13.5.2 to 13.5.5
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v13.5.2...v13.5.5)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: indirect
- dependency-name: next
  dependency-type: direct:production
...

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

package.json

@@ -26,7 +26,7 @@
     "graphql": "^15.8.0",
     "hls.js": "^1.3.2",
     "ioredis": "^5.3.2",
-    "next": "^13.5.2",
+    "next": "^13.5.5",
     "next-auth": "^4.22.0",
     "next-pwa": "^5.6.0",
     "nextjs-progressbar": "^0.0.16",