Chances are, one of the following two notifications are triggering that email:
- An issue is added to a project I'm on
- An issue is added to a project I own
If you are listed on the People tab of that request queue project, you can remove yourself (if not needed) which would eliminate the trigger for An issue is added to a project I'm on. If you are the request queue project owner, you could turn off that notification in your profile, but keep in mind that would impact all projects, and you would not be notified for any issue submitted under any project you own in Workfront.