It might happen that a given upgrade comes from multiple origins, in
which case the origins are separated by ", " and thus breaking
whitespace-based split. For example:
Inst package [1.2.3] (1.2.4 Debian:8.10/oldstable, Debian-Security:8/oldstable [amd64])
To workaround this case, mangle the apt-get output to remove whitespaces from
the origins list.