Fix parsing of execution time

execution/lag_analysis.py

@@ -11,7 +11,7 @@ exp_id =  sys.argv[1]
 benchmark = sys.argv[2]
 dim_value = sys.argv[3]
 instances = sys.argv[4]
-execution_minutes = sys.argv[5]
+execution_minutes = int(sys.argv[5])
 time_diff_ms = int(os.getenv('CLOCK_DIFF_MS', 0))
 
 #http://localhost:9090/api/v1/query_range?query=sum%20by(job,topic)(kafka_consumer_consumer_fetch_manager_metrics_records_lag)&start=2015-07-01T20:10:30.781Z&end=2020-07-01T20:11:00.781Z&step=15s