This has made it upstream and is in Fedora and RHEL9.

This is dead code that hasn't been included since F36.

sytemd-repart is in RHEL9 so let's start masking it and testing
it in RHCOS like we do in FCOS.

As part of this I had to move the system-configuration.yaml before
the ignition-and-ostree.yaml in the includes list because the
postprocess in the latter deletes everything in /etc/systemd/system/.

They are failing right now. See
coreos/fedora-coreos-tracker#1489

Note that we can't really deny these tests without hitting a bug
(feature?) in that if all tests in a kola run are denylisted kola
will exit with an error. Therefore we add the reprovision label to
a random test (`ext.config.boot.grub2-install`) so we'll have at
least one test run.