[Tails-l10n] Release schedule for Tails 3.8

Hi,

I'm the release manager for Tails 3.8.

My plan is:

* 2018-06-25: build and upload tentative 3.8 ISO image
* 2018-06-26: Test the tentative 3.8 ISO image
* 2018-06-26: Release

I *might* do the build & upload part earlier (and thus testing can
happen on the 25th too) but likely I'll prefer to have some kind of
week-end instead.

Usual manual testers: please tell me privately whether you're
available to test the ISO on June 26, ideally by 17:00 CEST.

Cheers,
--
intrigeri