pt-config-diff --pid broken on Ubuntu 20.04

Command to run to replicate:

Error:

Software:

OS: Ubuntu 20.04

MySQL: percona-server-server-5.7=5.7.42-46-1.focal

percona-toolkit: 3.5.7-1.focal

Where Daemon.pm is also provided by the percona-toolkit package:

Not sure when the bug was introduced but downgrading to percona-toolkit 3.5.0-5.focal fixes the problem.