update dag_run_id

csst_dag/message.py

-import json
 from astropy import time
 import numpy as np
 import string
-import os
 
 
-def gen_dag_run_id(digits=10):
+def gen_dag_run_id(digits=6):
     """
     Generate a unique run_id for a dag.
     """
     now = time.Time.now()
-    dag_run_id = now.iso[:10].replace("-", "")
+    dag_run_id = now.strftime("%Y%m%d-%H%M%S-")
 
     n = len(string.ascii_lowercase)
     for i in range(digits):