Add test that ensures subnet is usable after update

Adds a simple test to make sure a port can be created
on a subnet after disabling DHCP.

Related-Bug: #1573443
Change-Id: I94f1a59e52b109984904fd9e56e3c1a3f1c270fe
1 file changed
tree: 9f347f1e5540a21c11c91d786e1974666dd44ca9
  1. neutron/