[CI] Fix CI by addressing max_split_size_mb config (#3258)

### What this PR does / why we need it?
Fix CI by addressing max_split_size_mb config

### Does this PR introduce _any_ user-facing change?
No, test onyl

### How was this patch tested?
Full CI passed, espcially eagle one


- vLLM version: v0.10.2
- vLLM main:
https://github.com/vllm-project/vllm/commit/releases/v0.11.0

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

tests/e2e/singlecard/test_vlm.py

@@ -20,7 +20,6 @@
 
 Run `pytest tests/test_offline_inference.py`.
 """
-import os
 
 from vllm import SamplingParams
 from vllm.assets.audio import AudioAsset
@@ -28,9 +27,6 @@ from vllm.assets.image import ImageAsset
 
 from tests.e2e.conftest import VllmRunner
 
-os.environ["VLLM_WORKER_MULTIPROC_METHOD"] = "spawn"
-os.environ["PYTORCH_NPU_ALLOC_CONF"] = "max_split_size_mb:256"
-
 
 def test_multimodal_vl(prompt_template):
     image = ImageAsset("cherry_blossom") \