Fix pylint error in rest_example.py
Fix pylint error in rest_example.py

pylint says: "redefinition of unused 'HTTPKerberosAuth' from line 34"

Change-Id: Ie2b8cee42bf08eaa0e9bdab1ef5bf2b23ccee7f5

dpursehouse/pygerrit2,benjiii/pygerrit,sonyxperiadev/pygerrit,dpursehouse/pygerrit,markon/pygerrit2,gferon/pygerrit2,morucci/pygerrit