Change payload file path

Without this change, when running simultaneously, the size of the objects being written may be incorrect.

Signed-off-by: EESergey <[email protected]>

scenarios/preset/preset_grpc.py

@@ -33,7 +33,7 @@
 def main():
     container_list = []
     objects_struct = []
-    payload_filepath = '/tmp/data_file'
+    payload_filepath = '/tmp/data_file_' + args.size + 'k'
 
     endpoints = args.endpoint.split(',')