[CI] Upgrade trasnformers version (#6307)

Upgrade transformers to >=4.56.4

- vLLM version: v0.14.1
- vLLM main:
dc917cceb8

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>

tests/e2e/multicard/2-cards/test_ilama_lora_tp2.py

@@ -1,5 +1,4 @@
 import pytest
-from modelscope import snapshot_download  # type: ignore
 
 from tests.e2e.conftest import VllmRunner
 from tests.e2e.singlecard.test_ilama_lora import (EXPECTED_LORA_OUTPUT,
@@ -9,7 +8,7 @@ from tests.e2e.singlecard.test_ilama_lora import (EXPECTED_LORA_OUTPUT,
 @pytest.mark.parametrize("distributed_executor_backend", ["mp"])
 def test_ilama_lora_tp2(distributed_executor_backend, ilama_lora_files):
     with VllmRunner(
-            snapshot_download(MODEL_PATH),
+            MODEL_PATH,
             enable_lora=True,
             max_loras=4,
             dtype="half",