[Chore] Remove outdated transformers check (#20989)

Signed-off-by: Brayden Zhong <b8zhong@uwaterloo.ca>

Author: b8zhong

vllm/model_executor/models/idefics3.py

@@ -22,8 +22,8 @@
 
 import torch
 from torch import nn
-from transformers import (AddedToken, BatchFeature, Idefics3Config,
-                          Idefics3ImageProcessor, Idefics3Processor)
+from transformers import (BatchFeature, Idefics3Config, Idefics3ImageProcessor,
+                          Idefics3Processor)
 
 from vllm.config import VllmConfig
 from vllm.model_executor.layers.linear import ReplicatedLinear
@@ -199,21 +199,14 @@ def get_num_patches(
 
         return grid_w * grid_h + 1
 
-    # TODO: Remove after requiring transformers>=4.52
-    def _get_content(self, token: Union[AddedToken, str]) -> str:
-        if isinstance(token, str):
-            return token
-
-        return token.content
-
     def _get_image_token(
             self,
             processor: Optional[Idefics3Processor]) -> tuple[str, str, str]:
         if processor is None:
             processor = self.get_hf_processor()
 
-        image_token = self._get_content(processor.image_token)
-        fake_image_token = self._get_content(processor.fake_image_token)
+        image_token = processor.image_token
+        fake_image_token = processor.fake_image_token
         global_image_token = processor.global_image_tag
         return image_token, fake_image_token, global_image_token