Update v2.py

Fixed AttributeError: 'dict' object has no attribute 'split' #14344 this issue

fastapi/_compat/v2.py

@@ -262,7 +262,8 @@ def _replace_refs(
     new_schema = deepcopy(schema)
     for key, value in new_schema.items():
         if key == "$ref":
-            # ref_name = schema["$ref"].split("/")[-1]
+            print(f"schema:{schema}")
+            #ref_name = schema["$ref"].split("/")[-1]
             ref_name = schema["$ref"]            
             if isinstance(ref_value, str):
                 # Normal case
@@ -273,7 +274,6 @@ def _replace_refs(
             else:
                 # Unexpected type
                 ref_name = "invalid_ref"
-
             if ref_name in old_name_to_new_name_map:
                 new_name = old_name_to_new_name_map[ref_name]
                 new_schema["$ref"] = REF_TEMPLATE.format(model=new_name)