Update CHANGELOG.md (#2846)

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

Author: community-scripts-pr-app[bot]

CHANGELOG.md

@@ -27,6 +27,7 @@ All LXC instances created using this repository come pre-installed with Midnight
 
   - #### 🐞 Bug Fixes
 
+    - reveal.js: Update function now backs up index and config [@tremor021](https://github.com/tremor021) ([#2845](https://github.com/community-scripts/ProxmoxVE/pull/2845))
     - Changedetection: Increase RAM & Disk-Space [@MickLesk](https://github.com/MickLesk) ([#2838](https://github.com/community-scripts/ProxmoxVE/pull/2838))
     - Linkwarden: Optimze RUST Installation [@MickLesk](https://github.com/MickLesk) ([#2817](https://github.com/community-scripts/ProxmoxVE/pull/2817))
     - Nginx: Fix $STD for tar [@MickLesk](https://github.com/MickLesk) ([#2813](https://github.com/community-scripts/ProxmoxVE/pull/2813))