Investigate failing tests

[AyanSinhaMahapatra]

See tests disabled in d88c929

[AyanSinhaMahapatra]

Additionally:

On ubuntu tests in azure pipelines (but this passed locally on ubuntu):

FAILED tests/test_vmimage.py::TestExtractVmImage::test_can_listfs_from_qcow2_image - assert [('/dev/sda', 'ext2')] == [('libguestfs', "warning: current user is not a member of the KVM group (group ID 109). This user cannot access /dev/kvm, so libguestfs may run very slowly. It is recommended that you 'chmod 0666 /dev/kvm' or add the current user to the KVM group (you might need to log out and log in again)."), ('/dev/sda', 'ext2')]
FAILED tests/test_vmimage.py::TestExtractVmImage::test_can_extract_qcow2_vm_image_as_tarball - extractcode.ExtractErrorFailedToExtract: Failed to run guestfish to extract VM image: /usr/bin/guestfish --ro --format=qcow2 --add /tmp/scancode-tk-tests -6s1ibyb2/t03h85mz/foobar.qcow2.tar.gz/foobar.qcow2 run : mount libguestfs / : tar-out / /tmp/scancode-tk-tests -6s1ibyb2/1b97wz3s/vmimage/foobar.qcow2-libguestfs.tar.gz compress:gzip
output: libguestfs: warning: current user is not a member of the KVM group (group ID 109). This user cannot access /dev/kvm, so libguestfs may run very slowly. It is recommended that you 'chmod 0666 /dev/kvm' or add the current user to the KVM group (you might need to log out and log in again).
*stdin*:0: libguestfs: error: mount: mount_stub: libguestfs: No such file or directory
FAILED tests/test_vmimage.py::TestExtractVmImage::test_can_extract_qcow2_vm_image_not_as_tarball - extractcode.ExtractErrorFailedToExtract: Failed to run guestfish to extract VM image: /usr/bin/guestfish --ro --format=qcow2 --add /tmp/scancode-tk-tests -6s1ibyb2/bc69cxr_/bios-tables-test.x86_64.iso.qcow2.tar.gz/bios-tables-test.x86_64.iso.qcow2 run : mount libguestfs / : tar-out / /tmp/scancode-tk-3n4jt2uk/bios-tables-test.x86_64.iso.qcow2-libguestfs.tar.gz compress:gzip
output: libguestfs: warning: current user is not a member of the KVM group (group ID 109). This user cannot access /dev/kvm, so libguestfs may run very slowly. It is recommended that you 'chmod 0666 /dev/kvm' or add the current user to the KVM group (you might need to log out and log in again).
*stdin*:0: libguestfs: error: mount: mount_stub: libguestfs: No such file or directory

On macos arm, many tests were failing with:

Exception: 7zip not found. Please refer to the scancode-toolkit documentation on how to install 7zip for your system.

Even though we are installing system-provided plugins correctly and installing sevenzip with homebrew, maybe the installation location is different?

Also on ubuntu arm, there are slight changes in test expectations for 7zip extracted folders?

E             -     '/weird_names/winchr/ab*.t*',
E             +     '/weird_names/winchr/ab*_1.t*',
E             ?                             ++
E                   '/weird_names/winchr/ab/.t',
E                   '/weird_names/winchr/ab:.t:',
E                   '/weird_names/winchr/ab<.t<',
E                   '/weird_names/winchr/ab>.t>',
E             -     '/weird_names/winchr/ab?.t?',
E             +     '/weird_names/winchr/ab?_2.t?',
E             ?                             ++
E                   '/weird_names/winchr/ab|.t|',