test_integration_cluster.rb - fix get_worker_pids call
test_integration_cluster.rb - fix get_worker_pids call

test_worker_index_is_with_in_options_limit uses 3 workers, but get_worker_pids defaults to 2

eileencodes/puma,puma/puma,eileencodes/puma,eileencodes/puma,puma/puma,puma/puma,puma/puma,eileencodes/puma