Fixed wrong test arg order on redis_benchmarks_specification (#282)

* Fixed failing memtier args test

* Fixed wrong test arg order on redis_benchmarks_specification/__self_contained_coordinator__/clients.py

Author: fcostaoliveira

redis_benchmarks_specification/__self_contained_coordinator__/clients.py

@@ -7,13 +7,13 @@ def prepare_memtier_benchmark_parameters(
     oss_cluster_api_enabled,
 ):
     benchmark_command = [
+        "--json-out-file",
+        local_benchmark_output_filename,
         full_benchmark_path,
         "--port",
         "{}".format(port),
         "--server",
         "{}".format(server),
-        "--json-out-file",
-        local_benchmark_output_filename,
     ]
     if oss_cluster_api_enabled is True:
         benchmark_command.append("--cluster-mode")