* Use different package for DNF tests
Ninja caused errors in Fedora 30. This works in both Fedora 29 and 30.
* Fix git integration tests
Git >= 2.21.0 has either a bug or change in behavior where it errors when fetching a
repository containing submodules that are behind the upstream submodule commits.
It's weird and I don't fully understand it.
Get around this my checking out specific commits from a repository rather than
switch the origin URL.
* Fix PostgreSQL tests
The error message is slightly different
18feeb51a8