FogBugz supports integrating directly with GitHub to reference any commits that mention a FogBugz case in their commit messages. You can enable it for your team in the Avatar Menu > Integrations.
This integration can be enabled for one or more GitHub repositories that you choose. Once enabled, FogBugz will automatically create case events for any Git commits in those repositories that include the case number in the commit message, in the format of “case XYZ”.
The article Using Integrations in FogBugz provides more information about this topic.