Fix typing annotations for FSDP and DeepSpeed in TrainingArguments (#24549)

* Fix typing annotations for FSDP and DeepSpeed in TrainingArguments

* Change dict to Dict

src/transformers/training_args.py

@@ -976,7 +976,7 @@ class TrainingArguments:
             )
         },
     )
-    fsdp_config: Optional[str] = field(
+    fsdp_config: Optional[Union[str, Dict]] = field(
         default=None,
         metadata={
             "help": (
@@ -994,11 +994,11 @@ class TrainingArguments:
             )
         },
     )
-    deepspeed: Optional[str] = field(
+    deepspeed: Optional[Union[str, Dict]] = field(
         default=None,
         metadata={
             "help": (
-                "Enable deepspeed and pass the path to deepspeed json config file (e.g. ds_config.json) or an already"
+                "Enable deepspeed and pass the path to deepspeed json config file (e.g. `ds_config.json`) or an already"
                 " loaded json file as a dict"
             )
         },