[Misc] upgrade to vllm main (#6646)

### What this PR does / why we need it?
This PR upgrades the core vLLM dependency to a newer version from the
main branch (`13397841ab469cecf1ed425c3f52a9ffc38139b5`). This is
necessary to keep our project up-to-date with the latest features and
fixes from upstream vLLM.

1.
ac32e66cf9
pass file is moved.

- vLLM version: v0.15.0
- vLLM main:
d7e17aaacd

---------

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>
Signed-off-by: wxsIcey <1790571317@qq.com>
Signed-off-by: Meihan-chen <jcccx.cmh@gmail.com>
Co-authored-by: wxsIcey <1790571317@qq.com>

.github/workflows/_unit_test.yaml

@@ -72,7 +72,8 @@ jobs:
             --ignore tests/ut/kv_connector/test_remote_decode_lifecycle.py \
             --ignore tests/ut/core/test_scheduler_dynamic_batch.py \
             --ignore tests/ut/kv_connector/test_mooncake_connector.py \
-            --ignore tests/ut/worker/test_worker_v1.py
+            --ignore tests/ut/worker/test_worker_v1.py \
+            --ignore tests/ut/spec_decode/test_mtp_proposer.py
 
       - name: Upload coverage to Codecov
         # only upload coverage when commits merged