[qemu] error level logs are outputted when force stopping an instance

[sharder996]

Describe the bug
When you force stop an instance or delete purge it, Multipass outputs some scary logs that make it appear as if something went wrong. Happens on any platform running QEMU.

To Reproduce
multipass stop --force foo or multipass delete --purge foo

% multipass stop --force bar
[2024-07-16T21:31:50.536] [error] [bar] process error occurred Crashed program: qemu-system-aarch64; error: Process crashed
[2024-07-16T21:31:50.538] [error] [bar] error: program: qemu-system-aarch64; error: Process crashed

Expected behavior
No logs are outputted as the command has completed successfully