[CI] Fix test on pyhccl to 2 cards (vllm-project#2094)

### What this PR does / why we need it?
Fix test on pyhccl to 2 cards

### Does this PR introduce _any_ user-facing change?
N/A

### How was this patch tested?
CI passed with existing test.
- vLLM version: v0.10.0
- vLLM main:
vllm-project/vllm@0d0cc9e

Signed-off-by: MengqingCao <[email protected]>

Author: MengqingCao

tests/e2e/multicard/test_pyhccl_distributed.py

@@ -89,7 +89,7 @@ def worker_fn():
 
 
 def test_pyhccl():
-    distributed_run(worker_fn, 4)
+    distributed_run(worker_fn, 2)
 
 
 def broadcast_worker_fn():
@@ -118,4 +118,4 @@ def broadcast_worker_fn():
 
 
 def test_pyhccl_broadcast():
-    distributed_run(broadcast_worker_fn, 4)
+    distributed_run(broadcast_worker_fn, 2)