ban numpy multithreading

csst_common/pipeline.py

 import json
-import os.path
+import os
 import subprocess
 import warnings
 
@@ -59,6 +59,10 @@ class Pipeline:
         if filter_warnings:
             self.filter_warnings()
 
+    def ban_multithreading(self):
+        os.environ["OMP_NUM_THREADS"] = "1"
+        os.environ["MKL_NUM_THREADS"] = "1"
+
     def set_test_env(self):
         os.environ["CSST_DFS_API_MODE"] = "cluster"
         os.environ["CSST_DFS_GATEWAY"] = "172.24.27.2:30880"