Add conda-forge to Windows test workflow (to comply with upstream khiops-core)

TODO: Revert this just before merging PR #223

Author: popescu-v

.github/workflows/conda.yml

@@ -95,7 +95,7 @@ jobs:
       - name: Install the Khiops Conda package (Windows)
         if: runner.os == 'Windows'
         run: |
-          conda install --channel khiops-dev khiops-core=$KHIOPS_CORE_VERSION
+          conda install --channel conda-forge --channel khiops-dev khiops-core=$KHIOPS_CORE_VERSION
           conda install --override-channels --channel conda-forge --channel ./khiops-conda/ khiops
       # In Linux/macOS we need the conda-forge channel to install their pinned versions
       - name: Install the Khiops Conda package (Linux/macOS)