tails::tester: install python3-potr and python3-slixmpp
In tails!278 (merged) we have migrated otr-bot to Python 3 (refs: tails#17031 (closed)) which require these new deps.
Closes: sysadmin#17784 (closed)
In tails!278 (merged) we have migrated otr-bot to Python 3 (refs: tails#17031 (closed)) which require these new deps.
Closes: sysadmin#17784 (closed)