Fix sklearnex: force-reinstall scikit-learn-intelex after base image upgrade

Author: stevemessick

Dockerfile.tmpl

@@ -28,6 +28,8 @@ RUN uv pip install --no-build-isolation --no-cache --system "git+https://github.
 # b/468367647: Unpin protobuf, version greater than v5.29.5 causes issues with numerous packages
 RUN uv pip install --system --force-reinstall --no-cache --no-deps torchtune
 RUN uv pip install --system --force-reinstall --no-cache "protobuf==5.29.5"
+# b/493600019: New Colab base image may drop scikit-learn-intelex; re-install to ensure sklearnex is available.
+RUN uv pip install --system --force-reinstall --no-cache scikit-learn-intelex
 
 # Adding non-package dependencies:
 ADD clean-layer.sh  /tmp/clean-layer.sh