fix failing python unit test
fix failing python unit test

The problem was introduced by https://github.com/rpm-software-management/libdnf/pull/937
The PR added a new pkg with a require into the updates test repo
therefore their count increased.

rpm-software-management/libdnf,rpm-software-management/libdnf,rpm-software-management/libdnf,rpm-software-management/libdnf