(this is a RHEL clone of https://src.fedoraproject.org/rpms/grub2/pull-request/28)

When kernel-install is called for a UKI, 20-grub.install copies it to /boot
which is totally unneeded, UKIs are now handled by the standard systemd's
90-uki-copy.install (backported to RHEL as https://issues.redhat.com/browse/RHEL-16354)  correctly which places them to the ESP.