Upgrade to Torbirdy 0.2.5

Originally created by @Anonymous on #15600 (Redmine)

A user remarked that Tails uses Torbirdy from Stretch (0.2.1) while we should use TB from Unstable (0.2.5).
Tentatively assigning to FTeam.

Feature Branch: feature/15091-thunderbird-60

Edited May 15, 2020 by Anonymous

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