CBQE-0: fixing runsystest.py script, not to checkout testrunner on workers

Change-Id: I52704f2ff3bcc3a6c11eff43079f5d541bdce608
Reviewed-on: http://review.couchbase.org/42506
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>