Update Dockerfile.ci to install specific version of flashinfer-cubin (0.6.4) and ensure vllm installation remains intact.

Signed-off-by: tzhouam <tzhouam@connect.ust.hk>

docker/Dockerfile.ci

@@ -21,7 +21,7 @@ RUN apt-get update && \
 RUN uv pip install --system --upgrade --force-reinstall --prerelease=allow vllm --extra-index-url https://wheels.vllm.ai/a60985b07eaf0fefa4c353ad2309b745707591ed
 
 RUN uv pip install --system --no-cache-dir ".[dev]"
-
+RUN uv pip install --system --upgrade "flashinfer-cubin==0.6.4"
 RUN ln -sf /usr/bin/python3 /usr/bin/python
 
 ENTRYPOINT []