CI Fix lock-file update workflow (scikit-learn#30897)

Author: lesteve

.github/workflows/update-lock-files.yml

@@ -34,6 +34,7 @@ jobs:
         run: |
           source build_tools/shared.sh
           source $CONDA/bin/activate
+          conda update -n base --all
           conda install -n base conda conda-libmamba-solver -y
           conda config --set solver libmamba
           conda install -c conda-forge "$(get_dep conda-lock min)" -y