Remove 1 Patrole test with a hardcoded vxlan id

Remove 1 Patrole test with a hardcoded vxlan id

It may fail when testing OpenStack in production or when running
testcases in parallel [1] because vxlan 200 is hardcoded [2]

[1] http://artifacts.opnfv.org/functest/functest-opnfv-functest-smoke-hunter-patrole-run-75/results/patrole/tempest-report.html
[2] https://github.com/openstack/patrole/blob/master/patrole_tempest_plugin/tests/api/network/test_networks_rbac.py#L208

Change-Id: Ibfaed6f3a95d016790baafebd203e49e152a889b
Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>