Comment 1 for bug 1771928

Just a simple test which tries to create instant from 'bad' image uploaded to glance
show that disk space is lost. In my case it was ~= 800Mb image

root@shura-edge1:~# lsof -P 2>/dev/null | grep nova-com | grep /tmp
nova-comp 25306 nova 10u unix 0xffff88007795c000 0t0 2128952 /tmp/tmpybLoe9/privsep.sock type=STREAM
nova-comp 25306 nova 17u REG 253,1 884226169 10489 /tmp/tmpDcl9E7 (deleted)
nova-comp 25306 nova 18u REG 253,1 0 26813 /tmp/tmpGX3y7K (deleted)
nova-comp 25306 nova 26u REG 253,1 884226169 56992 /tmp/tmpWMDoKu (deleted)
nova-comp 25306 nova 27u REG 253,1 0 57308 /tmp/tmp4eR46t (deleted)
nova-comp 25306 nova 30u REG 253,1 884226169 57334 /tmp/tmpFTMcjK (deleted)
nova-comp 25306 nova 31u REG 253,1 0 57394 /tmp/tmpfZOfB1 (deleted)