[Minor] Fix test_cache.py CI test failure (vllm-project#2684)

Author: pcmoritz

tests/kernels/test_cache.py

@@ -200,12 +200,12 @@ def test_swap_blocks(
 
     # Create the KV caches on the first device.
     src_key_caches, src_value_caches = kv_cache_factory(
-        num_blocks, block_size, 1, num_heads, head_size, dtype, seed,
+        num_blocks, block_size, 1, num_heads, head_size, dtype, None, seed,
         src_device)
 
     # Create the KV caches on the second device.
     dist_key_caches, dist_value_caches = kv_cache_factory(
-        num_blocks, block_size, 1, num_heads, head_size, dtype, seed,
+        num_blocks, block_size, 1, num_heads, head_size, dtype, None, seed,
         dst_device)
 
     src_key_caches_clone = src_key_caches[0].clone()