XYZ Network- Close ssh connection between tests.

This change includes:
    1. Close ssh connection after each test.
    2. Send valid gateway details while testing prefix length.

This resolves openbmc/openbmc-test-automation#1060

Change-Id: I904ae05b7e91e2196c1f1b1be656689e7fdb96b1
Signed-off-by: Prashanth Katti <prkatti1@in.ibm.com>
1 file changed