[Bugfix] Fix 3.12 builds on main (#8510)

Signed-off-by: Joe Runde <Joseph.Runde@ibm.com>

Dockerfile

@@ -182,10 +182,6 @@ FROM vllm-base AS test
 ADD . /vllm-workspace/
 
 # install development dependencies (for testing)
-# A newer setuptools is required for installing some test dependencies from source that do not publish python 3.12 wheels
-# This installation must complete before the test dependencies are collected and installed.
-RUN --mount=type=cache,target=/root/.cache/pip \
-    python3 -m pip install "setuptools>=74.1.1"
 RUN --mount=type=cache,target=/root/.cache/pip \
     python3 -m pip install -r requirements-dev.txt
 

requirements-common.txt

@@ -29,4 +29,5 @@ importlib_metadata
 mistral_common >= 1.4.0
 pyyaml
 six>=1.16.0; python_version > '3.11' # transitive dependency of pandas that needs to be the latest version for python 3.12
+setuptools>=74.1.1; python_version > '3.11' # Setuptools is used by triton, we need to ensure a modern version is installed for 3.12+ so that it does not try to import distutils, which was removed in 3.12
 einops # Required for Qwen2-VL.