Simplify Mattermost help description

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: metalllinux

docs/guides/contribute/contributing.md

@@ -1387,7 +1387,7 @@ git push origin your-new-document
 
 ## Getting Help
 
-- **Mattermost**: Join the [Documentation channel](https://chat.rockylinux.org/rocky-linux/channels/documentation) and the community of contributors will be more than happy to help you with your document: whether that be with your local editing setup to content review and formatting.
+- **Mattermost**: Join the [Documentation channel](https://chat.rockylinux.org/rocky-linux/channels/documentation) and the community of contributors will be more than happy to help you with your document.
 - **GitHub Issues**: Report documentation bugs or suggest improvements
 - **Forums**: Visit the [Rocky Linux Forums](https://forums.rockylinux.org) for general questions