[Tails-l10n] Release schedule for Tails 6.9

Hi,

intrigeri will be the RM for Tails 6.9

The current plan is:

- Wednesday, 2024-10-30: build images, start testing
- Thursday, 2024-10-31: release

Developers, please:

   - Book time for automated and manual QA during office hours,
     from Wednesday 15:00 to Thursday 11:00 (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.

Cheers!