Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -6,7 +6,7 @@ Thank you for your interest in contributing to Mattermost. This guide provides a
 
 1. Review the list of [Good First Contribution](https://mattermost.atlassian.net/issues/?filter=10206) tickets listed in Jira.
     - You are welcome to work on any ticket, even if it is assigned, so long as it is not yet marked "in progress"
-    - (optional) You can share with the community that you're working on a specific ticket so no one else inadvertently duplicates your work by sharing on the forum or in the core team Mattermost instance as described in step 3. 
+    - (optional) Comment on the ticket that you're starting so no one else inadvertently duplicates your work
 
 2. These projects are intended to be a straight forward first pull requests from new contributors. 
   - If you don't find something appropriate for your interests, please see the full list of tickets [Accepting Pull Requests](https://mattermost.atlassian.net/issues/?filter=10101).