Do not retain NetconfConnectModule reference

Anononymous classes retain a reference to the module, which means we
leak quite a bit of memory if the client is not shut down.

Change-Id: Ifeaeb383afe8ff5c899cee66ea861e30bdf2ae41
Signed-off-by: Robert Varga <rovarga@cisco.com>
Merge "Do not retain NetconfConnectModule reference"