Errors with collecting logs for Machine with tests adopted from CAPI

[mboukhalfa]

What steps did you take and what happened:
Clusterctl upgrade test reused from CAPI persistently show the errors:

Failed to get logs for Machine clusterctl-upgrade-w6i26f-4d75h, Cluster clusterctl-upgrade-8o9j0d/clusterctl-upgrade-w6i26f: error finding the serial log: stat /var/log/libvirt/qemu/clusterctl_upgrade_8o9j0d/node_1-serial0.log: no such file or directory
05:56:59  Failed to get logs for Machine clusterctl-upgrade-w6i26f-xm89z-rfgwr, Cluster clusterctl-upgrade-8o9j0d/clusterctl-upgrade-w6i26f: error finding the serial log: stat /var/log/libvirt/qemu/clusterctl_upgrade_8o9j0d/node_0-serial0.log: no such file or directory
05:56:59  Failed to get infrastructure logs for Cluster clusterctl-upgrade-8o9j0d/clusterctl-upgrade-w6i26f: CollectInfrastructureLogs not implemented 

This msg seen also when trying to reuse other tests like md-remediation

What did you expect to happen:
Show that machine logs got successfully collected !

Anything else you would like to add:

Upon inspection of the collected tarball, I found the machine log files under the qemu folder. However, I am unsure if they were collected correctly despite the error message in the logs.

/kind bug

[Rozzii]

/triage accepted