Workaround broken pyroute2 0.5.13

The pyroute2 package version 0.5.13 introduced a bug[1] that breaks
amphora. Unfortunately neutron needs a different fix that is in 0.5.13,
so we are going to work around the problem until we can get pyroute2 fixed.

This patch uninstalls pyroute2 and installs version 0.5.12.

[1] svinota/pyroute2#724

Change-Id: I365d719810de792213da47ebafa46e7e0fd2e9fa

elements/amphora-agent/install.d/amphora-agent-source-install/75-amphora-agent-install

@@ -16,6 +16,12 @@ $AMP_VENV/bin/pip install pip --upgrade
 
 $AMP_VENV/bin/pip install -U -c /opt/upper-constraints.txt /opt/amphora-agent
 
+# Workaround https://github.com/svinota/pyroute2/issues/724
+# TODO(johnsom) Remove once a that is resolved and 0.5.13 has been blocked in
+# global requirements.
+$AMP_VENV/bin/pip uninstall -y pyroute2
+$AMP_VENV/bin/pip install pyroute2==0.5.12
+
 # Link the amphora-agent out to /usr/local/bin where the startup scripts look
 ln -s $AMP_VENV/bin/amphora-agent /usr/local/bin/amphora-agent || true