Stop memcached properly to avoid errors on hebe
Stop memcached properly to avoid errors on hebe

Change-Id: Ic1a6b0b6cb8e2a94c6e92c6bd188f10f9ed3b191
Reviewed-on: https://review.couchbase.org/c/perfrunner/+/179452
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Daniel Nagy <8d5a66e0b9d9f09515b5499449a5435e905f875d@couchbase.com>

couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner