Bug#815564: borgbackup: activate unittests during build

[Gianfranco Costamagna]

Hi

>→ Green lights from my end, git/master-testing-enabled builds went

>through just fine.


the package is already on deferred/5, it will reach backports in 4 days 23 
hours now

https://ftp-master.debian.org/deferred.html

cheers,

Gianfranco