🔧 refactor(documentloaders.py): use Optional type hint for name parameter in format_field method

The `name` parameter in the `format_field` method of the `DocumentLoaderFrontNode` class now uses the `Optional` type hint to indicate that it can be None. This improves the code's readability and makes it easier to understand the expected behavior of the method.

src/backend/langflow/template/frontend_node/documentloaders.py

@@ -1,3 +1,4 @@
+from typing import Optional
 from langflow.template.field.base import TemplateField
 from langflow.template.frontend_node.base import FrontendNode
 
@@ -106,7 +107,7 @@ class DocumentLoaderFrontNode(FrontendNode):
         )
 
     @staticmethod
-    def format_field(field: TemplateField, name: str | None = None) -> None:
+    def format_field(field: TemplateField, name: Optional[str] = None) -> None:
         FrontendNode.format_field(field, name)
         if field.name == "metadata":
             field.show = True