Remove duplicate dependency declarations

org.opendaylight.controller:networkconfig.neutron and
org.opendaylight.yangtools:features-test are declared twice in the pom
file causing Maven to throw warnings.

Change-Id: I32da02be41a5a51ad05c85a0e186549141f38513
Signed-off-by: Thanh Ha <thanh.ha@linuxfoundation.org>