Depsolver test that starts a temporary file server and queries it using
osbuild-depsolve-dnf.
Generates all combinations of repositories configured through the
depsolve-dnf request or the repositories directory and runs the test
cases. The results should be the same regardless of combination.
Test repos are defined with a fake gpg key on the request or repo config
and check if it is read correctly and attached to the repo configs in
the response. The name of the repo is appended to each repo's gpg key
so we can make sure that repo option values don't get swapped.
