Make directory exist ok for ray spinning up multiple replicas on a single instance (#33604)

Signed-off-by: Jiang Wu <jwu@cclgroup.com>

vllm/transformers_utils/runai_utils.py

@@ -64,9 +64,7 @@ class ObjectStorageModel:
             "model_streamer",
             hashlib.sha256(str(url).encode()).hexdigest()[:8],
         )
-        if os.path.exists(dir_name):
-            shutil.rmtree(dir_name)
-        os.makedirs(dir_name)
+        os.makedirs(dir_name, exist_ok=True)
         self.dir = dir_name
         logger.debug("Init object storage, model cache path is: %s", dir_name)