[V0 Deprecation] Remove VLLM_USE_V1 from tests (#26341)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

tests/v1/core/test_kv_sharing.py

@@ -1,11 +1,14 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
+import pytest
 import torch
 
 from vllm.v1.kv_cache_interface import FullAttentionSpec, KVCacheGroupSpec
 from vllm.v1.worker.utils import add_kv_sharing_layers_to_kv_cache_groups
 
+pytestmark = pytest.mark.cpu_test
+
 
 def new_kv_cache_spec():
     return FullAttentionSpec(16, 1, 1, torch.float32, False)