Bug#1122161: undertime: please replace the transitional python3-tz dependency with python3-pytz

[Alexandre Detiste]

Source: undertime
Version: 4.3.0
Severity: normal

Dear Maintainer,

Nowadays python3-tz is an empty package that does nothing but pulling in 
python3-pytz.

Please depends on this new package directly.

Greetings

Alexandre