If the network is in Openstack it is needed to be deployed

#### Reviewers
@jframos @jesuspg

#### Description
if the network exists in Openstack, the paas manager does not have to deploy it
https://jira.tid.es/browse/CLAUDIA-4453
#### Test
Tested locally agains experimentacion testbed
For sure it is private, but it is not a reason why do you not include a javadoc specially in this function due to it is used in the rest and it is important to know what do you do here.