depends option test regression

[LyzardKing]

There's a branch with the --depends option, that lists the needed (or installed) dependencies.
This introduced a regression in the tests, so it will not be merged until it's fixed.
If someone wants to have a go at finding the issue the branch is https://github.com/ubuntu/ubuntu-make/tree/list_depends
Closes #610