Connection to config subsystem netconf endpoint refused

https://jenkins.opendaylight.org/releng/view/bgpcep/job/bgpcep-csit-3node-periodic-bgpclustering-only-boron/

in builds #19 and #20 it is done well

used feature: odl-netconf-clustered-topology

this job tries configure netconf device via restconf firstly and then using this device to configure bgp peer

after PUT restconf/config/network-topology:network-topology/topology/topology-netconf/node/peer-controller-config
<node xmlns="urn:TBD:params:xml:ns:yang:network-topology"> <node-id>peer-controller-config</node-id> <host xmlns="urn:opendaylight:netconf-node-topology">10.29.9.33</host> <port xmlns="urn:opendaylight:netconf-node-topology">1830</port> <username xmlns="urn:opendaylight:netconf-node-topology">admin</username> <password xmlns="urn:opendaylight:netconf-node-topology">admin</password> <tcp-only xmlns="urn:opendaylight:netconf-node-topology">false</tcp-only> <keepalive-delay xmlns="urn:opendaylight:netconf-node-topology">0</keepalive-delay> </node>
response with status code 200 is received.

Now the problem is that GET restconf/config/network-topology:network-topology/topology/topology-netconf/node/peer-controller-config/yang-ext:mount
never receives status 200

This happened also in the past. The reason was the within some akka timeout some processes or dependencies were not completed. As a workaround the test suite tried 3 times to configure that device in the following loop
1) PUT to configure device
2) GET for 30s check if mounted
3a) DELETE device if not mounted;
3b) continue configuring bgp peer if netconf device mounted

The problem now is that even that workaround stopped working.