dnf5 (in obsoleting-dnf mode) provides /usr/bin/yum and obsoletes
yum, so we should drop the 'dnf-yum' entries (which installed
yum). dnf5 also appears to provide and obsolete microdnf, so we
should replace microdnf with dnf5 in the minimal image, I guess.
dnf5-plugins seems the logical replacement for dnf-plugins-core
(which is not removed yet, but is specific to dnf4).
Signed-off-by: Adam Williamson <awilliam@redhat.com>
