bridge not created if it's configured northbound while ovs node is disconnected

If the connection between the plugin and ovs node is not active when a
configuration is requested via northbound rest api, that configuration will
not be made to the ovs node when it reconnects.

to recreate:

1. connect ovs to controller
sudo ovs-vsctl set-manager tcp:${IP}:6640

2. create connection in config store to match that as seen in
operational.

3. create a bridge in config store and verify it's there in operational
and on ovs node

4. disconnect ovs node (iptables can be used to block traffic OUT on
port 6640, or just a reboot of ovs node)

5. while disconnected, create a new bridge in config store

6. reconnect ovs node and the configuration from 3 will still be there
in operational as well as on ovs node, but the config made in 5 will
not.