update PVC access mode to ReadWriteMany for shared storage

Author: aishwaryaraimule21

examples/pytorch/text-classification/Fine-Tune-Llama3-LLM.ipynb

@@ -303,7 +303,7 @@
     "    provision_model_storage = kubernetes.CreatePVC(\n",
     "        # can also use pvc_name instead of pvc_name_suffix to use a pre-existing PVC\n",
     "        pvc_name='storage-initializer',\n",
-    "        access_modes=['ReadWriteOnce'],\n",
+    "        access_modes=['ReadWriteMany'],\n",
     "        size='100Gi',\n",
     "        storage_class_name='nfs-storage',\n",
     "    )\n",