If ext net is not found, skip the vm2vm tests

No need to create a fake ext net since the connectivity to
it will not work anyway. The correct way at the real envs
is to skip the vm2vm tests in case the external network
is not found.

Related-PROD: PROD-36943
Change-Id: Id45f226834fea56bb93b0a93dc8295a598023c53
diff --git a/fixtures/base.py b/fixtures/base.py
index 83d0be6..076fa3c 100644
--- a/fixtures/base.py
+++ b/fixtures/base.py
@@ -78,6 +78,10 @@
     )
     os_resource['net1'] = os_actions.create_network_resources()
     os_resource['ext_net'] = os_actions.get_external_network()
+    if not os_resource['ext_net']:
+        pytest.skip("External network not found, skipping tests. Please set "
+                    "the existing floating network at the 'external_network' "
+                    "option in the global_config.yaml file.")
     adm_project = os_actions.get_project_by_name("admin")
     os_resource['router'] = os_actions.create_router(
         os_resource['ext_net'], adm_project.id)
@@ -116,8 +120,6 @@
     openstack_clients.compute.keypairs.delete(os_resource['keypair'].name)
     if flavor_is_created:
         openstack_clients.compute.flavors.delete(os_resource['flavor_id'])
-    if os_actions.create_fake_ext_net:
-        openstack_clients.network.delete_network(os_resource['ext_net']['id'])
 
 
 @pytest.fixture(scope='session')
@@ -180,6 +182,10 @@
     os_resource_alt_project['net1'] = alt_os_actions.create_network_resources(
         project=alt_project.name, cidr='10.3.7.0/24')
     os_resource_alt_project['ext_net'] = alt_os_actions.get_external_network()
+    if not os_resource_alt_project['ext_net']:
+        pytest.skip("External network not found, skipping tests. Please set "
+                    "the existing floating network at the 'external_network' "
+                    "option in the global_config.yaml file.")
 
     os_resource_alt_project['router'] = alt_os_actions.create_router(
         os_resource_alt_project['ext_net'], alt_project.id)
@@ -213,9 +219,6 @@
     if flavor_is_created:
         openstack_alt_clients.compute.flavors.delete(
             os_resource_alt_project['flavor_id'])
-    if alt_os_actions.create_fake_ext_net:
-        openstack_alt_clients.network.delete_network(
-            os_resource_alt_project['ext_net']['id'])
 
     if alt_os_actions.is_project_empty(alt_project.id):
         openstack_alt_clients.auth.projects.delete(alt_project.id)