fix: Remove opencv-python-headless from TensorRT-LLM image

[mc-nv]

Description

New OSRB guidance makes opencv-python-headless an immediate blocker for new releases. The TensorRT-LLM backend pulls the package in transitively through the tensorrt_llm wheel installed in dockerfile/Dockerfile.triton.trt_llm_backend, so it lands in the Triton TensorRT-LLM container image.

This removes the package in the same layer where tensorrt_llm is installed, running pip3 uninstall -y opencv-python-headless on both install paths (the PYPI_EXTRA_VALUES branch and the public pypi.nvidia.com branch). The || true guard keeps the build green when the package is not present.

Changes

• dockerfile/Dockerfile.triton.trt_llm_backend: uninstall opencv-python-headless in the same RUN layer as the tensorrt_llm install, on both the extra-values and public-wheel branches.

Related Issues:

• Resolves: TRI-1564

^{CI (internal): [#57992661](http://tritonserver.local/ci/pipelines/57992661)}