Bug#972787: picard: Aborts if directory scan finds a directory which cannot be read

[Ian Campbell]

Control: found -1 2.4.1-1

Hi (again),

I was able to fix the issue by monkey patching in an "except
PermissionError: pass" around line 549
of /usr/lib/picard/picard/tagger.py, in the existing try block around
the os.scandir.

FWIW this issue was already present in 2.4.1-1 but I upgraded to latest
and reconfirmed the issue still existing before reporting.

Thanks,
Ian.