fix bug of pg resource leak

Author: yexin

checkpoint_engine/distributed/hccl.py

@@ -228,6 +228,8 @@ def destroy_process_group(
             return
 
         self.pyhccl.destroy_comm()
+        self.pyhccl = None
+        self.pg = None
         self.initialized = False
 
 

checkpoint_engine/distributed/nccl.py

@@ -146,7 +146,6 @@ def destroy_process_group(
             return
 
         self.pynccl.destroy_comm()
-
         self.pynccl = None
         self.pg = None
         self.initialized = False