Call addCleanup(delete_server) immediately after resize server

addCleanup(delete_server) should be called immediately after
resizing server, otherwize if something goes wrong in the
following steps, the testcase will return without deleting server,
and thus may affect other resize testcases

Change-Id: Iaa51549f169414a24d622d0b31c983c9d0751176
1 file changed