Can you check
# dnf provides /usr/bin/kernel-install
I guess you’ll see systemd-udev-239-45.el8_4.1.x86_64 listed twice and systemd-udev-239-45.el8_4.2.x86_64 is missing…
Compare Cannot update puppet-agent to 6.24.0 on foreman servers
Looks like a bigger problem to me, not even related only to EL8…