[Tails-l10n] Release schedule for Tails 6.15

Hi,

intrigeri will be the RM for Tails 6.15.

The current plan is:

- Wednesday, April 30: build images, start testing
- Thursday, May 1st: release

Developers, please:

   - Book time for automated and manual QA during office hours,
     from Wednesday 13:00 to 18:00 (Europe/Berlin).
     If you can't, please let the RM know.

   - During these 2 days, don't push any change to the branch
     used for the release.

--
boyska (he/him)