btrfs: skip squota incompatible tests

These tests cannot succeed if mkfs enable squotas, as they either test
the specifics of qgroups behavior or they test *enabling* squotas. Skip
these in squota mode.

Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>