flake.lock: Updating 'revealjs (hakimel/reveal.js)' - 0c9bdeab -> 724c4fee (#398)

### Changes for revealjs

On branch: master
Commits: 0c9bdeab70...724c4fee27

- [006b348e](006b348e6b) reduce fragment style specificity, add custom class to reset fragment styles [hakimel/reveal.js⁠#2927](http://r.duckduckgo.com/l/?uddg=https://github.com/hakimel/reveal.js/issues/2927)
- [724c4fee](724c4fee27) build latest css

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

flake.lock

@@ -324,11 +324,11 @@
     "revealjs": {
       "flake": false,
       "locked": {
-        "lastModified": 1677460223,
-        "narHash": "sha256-4Wfy1iD5RaJiU2ub1Dh4zp4UDp1/PNhuck1FDgvvfds=",
+        "lastModified": 1678242855,
+        "narHash": "sha256-T9btOHiOdvhC1JijcfGOBc84miAbEb7CWd1Wvzae5m8=",
         "owner": "hakimel",
         "repo": "reveal.js",
-        "rev": "0c9bdeab70cef5c83216132660b60b78ecf82f69",
+        "rev": "724c4fee274914dd2d997b7584cf603c44e96c72",
         "type": "github"
       },
       "original": {