I experienced the same issue as described here but managed to solve it.
I ssh’d to the host and pulled the new image manually. When the download is finished the update works as expected using the frontend.
docker pull ghcr.io/home-assistant/qemux86-64-homeassistant:2022.4.7
I just rebooted my host and the error is gone.
That was the solution for me too
For me case closed, I tried a reboot of the Core, Supervisor but never rebooted the Host. Just did and update went fine.
Thanks guys, looks like it was a server-side issue and is now working. I was able to update just now without issue.