Fix gate failures

Neutron now enables the OVSDB native interface by default [1].
As a result, the neutron-ovs-cleanup command hangs when run
during stack.sh with OVN. The command was being run as part of
DevStack neutron OVS bridge setup and neutron L3 agent setup.
Since the command does not appear to be necessary, this patch
set overrides the command within the networking-ovn DevStack
plugin.

Also, neutron unit tests import testresources. To get tox py27
and py34 working correctly, testresources must be added to the
requirements. This fix was copied from [2].

[1] https://review.openstack.org/#/c/299655/
[2] https://review.openstack.org/#/c/336137/

Co-Authored-By: Amitabha Biswas <abiswas@us.ibm.com>

Change-Id: I6d934efe871d270bee07627394e2879ad9f56c06

devstack/override-defaults

@@ -18,3 +18,11 @@ fi
 function neutron_plugin_install_agent_packages {
     :
 }
+
+# NOTE(rtheis): Override the neutron-ovs-cleanup command run as part of
+# DevStack neutron OVS bridge setup and neutron L3 agent setup. The command
+# does not appear to be needed and hangs when running stack.sh because it
+# uses the OVSDB native interface.
+function neutron-ovs-cleanup {
+    :
+}

test-requirements.txt

@@ -11,6 +11,7 @@ oslosphinx!=3.4.0,>=2.5.0 # Apache-2.0
 doc8 # Apache-2.0
 oslotest>=1.10.0 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD
+testresources>=0.2.4 # Apache-2.0/BSD
 testscenarios>=0.4 # Apache-2.0/BSD
 WebTest>=2.0 # MIT
 testtools>=1.4.0 # MIT