The service desk e-mail is public if the issue tracker is public
### Summary
The service desk e-mail is public if the issue tracker is public
### Steps to reproduce
- Enable service desk
- Make the issue tracker available for anyone
- In a browser window not logged into gitlab, navigate to the repo, issues then service desk
- The page says: "Have your users email *redacted*@incoming.gitlab.com*
### Example Project
https://gitlab.com/zerodogg/gitlab-issue-service-desk-public/issues/service_desk
### What is the current *bug* behavior?
E-mail is publicly displayed.
### What is the expected *correct* behavior?
The e-mail shouldn't be publicly displayed. The documentation for service desk states "We recommend **putting this behind an alias** so that it can be changed if needed". This can't be done since gitlab itself publicizes the address to everyone (at least not without making the entire issue feature private).
issue