Remove unittest assuming file disks are not exportable
Remove unittest assuming file disks are not exportable

Signed-off-by: Aaron Karper <99cc1031546340b2b8ced5fe338b5890677a56ca@google.com>
Reviewed-by: Hrvoje Ribicic <be5828fca31f89218048bec4189e30a581aa65da@google.com>

leshchevds/ganeti,ganeti/ganeti,ganeti/ganeti,andir/ganeti,yiannist/ganeti,mbakke/ganeti,bitemyapp/ganeti,leshchevds/ganeti,leshchevds/ganeti,yiannist/ganeti,dimara/ganeti,yiannist/ganeti,andir/ganeti,ganeti/ganeti,onponomarev/ganeti,mbakke/ganeti,grnet/snf-ganeti,bitemyapp/ganeti,mbakke/ganeti,dimara/ganeti,grnet/snf-ganeti,onponomarev/ganeti,andir/ganeti