[Tails-l10n] Release schedule for Tails 5.9

Hi,

At this stage we don't know when we'll release Tails 5.9:
there's no Tor Browser release calendar for 2023 Q1 yet.

However, judging by recent experience, chances are that it happens
on 2023-01-24, 1 week after the Firefox 102.7 release.

We don't know who'll be the RM yet.

Dear manual testers, please let tails-rm@??? know how much
testing you can do on:

- Monday, January 23: afternoon/evening CET
- Tuesday, January 24: morning CET

Thanks in advance!

Cheers,
--
intrigeri