Convert formatting to use ruff instead of yapf + isort (#26247)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

tests/entrypoints/llm/test_prompt_validation.py

@@ -8,12 +8,12 @@ from vllm import LLM
 
 def test_empty_prompt():
     llm = LLM(model="openai-community/gpt2", enforce_eager=True)
-    with pytest.raises(ValueError, match='decoder prompt cannot be empty'):
+    with pytest.raises(ValueError, match="decoder prompt cannot be empty"):
         llm.generate([""])
 
 
 @pytest.mark.skip_v1
 def test_out_of_vocab_token():
     llm = LLM(model="openai-community/gpt2", enforce_eager=True)
-    with pytest.raises(ValueError, match='out of vocabulary'):
+    with pytest.raises(ValueError, match="out of vocabulary"):
         llm.generate({"prompt_token_ids": [999999]})