fix mgpu finalize issue

configs/metadata.json

@@ -1,7 +1,8 @@
 {
     "schema": "https://github.com/Project-MONAI/MONAI-extra-test-data/releases/download/0.8.1/meta_schema_20220324.json",
-    "version": "0.4.6",
+    "version": "0.4.7",
     "changelog": {
+        "0.4.7": "fix mgpu finalize issue",
         "0.4.6": "enable deterministic training",
         "0.4.5": "add the command of executing inference with TensorRT models",
         "0.4.4": "adapt to BundleWorkflow interface",

configs/multi_gpu_evaluate.json

@@ -26,6 +26,6 @@
         "$@validate#evaluator.run()"
     ],
     "finalize": [
-        "$dist.destroy_process_group()"
+        "$dist.is_initialized() and dist.destroy_process_group()"
     ]
 }

configs/multi_gpu_train.json

@@ -38,6 +38,6 @@
         "$@train#trainer.run()"
     ],
     "finalize": [
-        "$dist.destroy_process_group()"
+        "$dist.is_initialized() and dist.destroy_process_group()"
     ]
 }