Very long boot up in Ubuntu 20.04

I'd install Ubuntu 20.04 off the scratch. It looks like your "upgrade" borked something. "systemd-analyze blame" shows exactly, where your time goes... And waiting for mySql for a minute does not make sense at all. My output for udisk2 for example is

406ms udisks2.service

So save your data and install it freshly.

As a next step, you may look up the logs of mysql and udisks2, as they seem to take the longest here.

The command journalctl -b -u udisks2 -u mysql should be useful for that.