Update link to Docker Community Slack

Signed-off-by: Mathieu Champlon <[email protected]>

.github/ISSUE_TEMPLATE.md

@@ -20,7 +20,7 @@ The GitHub issue tracker is for bug reports and feature requests.
 General support can be found at the following locations:
 
 - Docker Support Forums - https://forums.docker.com
-- Docker Community Slack - https://dockr.ly/community
+- Docker Community Slack - https://dockr.ly/slack
 - Post a question on StackOverflow, using the Docker tag
 
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