Tails Installer is not available for Ubuntu artful (17.10)

Thanks to a user report, and reproduced by me, when trying to add tails-installer reporsitory in Ubuntu 17.10 we get the following error message:

The repository ‘http://ppa.launchpad.net/tails-team/tails-installer/ubuntu artful Release’ doesn’t have a Release file.

so impossible to fetch Tails Installer.

Original created by @mercedes508 on 14981 (Redmine)

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information