[CI/Build] Fix version conflict on transformers (#1490)

### What this PR does / why we need it?
Fix version conflict on transformers:
`pip._vendor.pkg_resources.ContextualVersionConflict: (transformers
4.53.0 (/usr/local/python3.10.17/lib/python3.10/site-packages),
Requirement.parse('transformers<4.53.0'), {'vllm-ascend'})`
Fix
https://github.com/vllm-project/vllm-ascend/actions/runs/15933263325/job/44947231642

### Does this PR introduce _any_ user-facing change?
Fix broken build

### How was this patch tested?
CI passed with new existing test.

Signed-off-by: MengqingCao <cmq0113@163.com>

pyproject.toml

@@ -20,6 +20,6 @@ requires = [
     "quart",
     "numba",
     # Remove after https://github.com/vllm-project/vllm-ascend/issues/1470
-    "transformers<4.53.0",
+    "transformers==4.52.4",
 ]
 build-backend = "setuptools.build_meta"

requirements.txt

@@ -27,4 +27,4 @@ numba
 torch-npu==2.5.1.post1.dev20250619
 
 # Remove after https://github.com/vllm-project/vllm-ascend/issues/1470
-transformers<4.53.0
+transformers==4.52.4