Introduce execution restriction on nsx-t-neutron-network-create task

Deployment task nsx-t-neutron-network create make two tenant networks
that are used for OSTF checks (test launch instances in internal network
and verify that VMs can successfulyy reach each other and external IP
addresses).

Root cause of the problem is that if we try to create networks twice
(run deployment task two times) it will fail with error that
"physical_network_type does not support being update". It is not
possible to run this task twice, to avoid such behaviour YAQL condition
prevents task from being run no more than one time. Task is executed
only when 'quantum' value (which determines that Neutron is enabled for
current environment) is changed, which should not happen during normal
operation (it is possible to switch this setting via fuel CLI, but not
through web UI).

Change-Id: Idd3000cdec0ef0c990c352d2cb7814fb4743d6f2
Closes-bug: #1626927

deployment_tasks.yaml

@@ -247,7 +247,7 @@
     timeout: 120
 
 - id: nsx-t-neutron-network-create
-  version: 2.0.0
+  version: 2.1.0
   type: puppet
   groups:
     - primary-controller
@@ -257,6 +257,8 @@
     - nsx-t-primary-neutron-server-start
     - nsx-t-configure-agents-dhcp
     - primary-openstack-network-agents-metadata
+  condition:
+    yaql_exp: "changed($.quantum)"
   parameters:
     puppet_manifest: puppet/manifests/neutron-network-create.pp
     puppet_modules: puppet/modules