Bump actions/download-artifact from 2 to 4.1.7 in /.github/workflows

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 2 to 4.1.7.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v2...v4.1.7)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/main.yml

@@ -113,7 +113,7 @@ jobs:
           [ $RUNNER_OS == macOS ] && export CONDA_PKGS_DIRS=~/.pkgs
           ${CONDA_EXE:-conda} create -y -p ./conda conda=${{ matrix.cver }}
     - name: Download the build artifact
-      uses: actions/download-artifact@v2
+      uses: actions/download-artifact@v4.1.7
       with:
         name: package-${{ github.sha }}
         path: ./conda/conda-bld
@@ -146,7 +146,7 @@ jobs:
       with:
         fetch-depth: 0
     - name: Download the build artifacts
-      uses: actions/download-artifact@v2
+      uses: actions/download-artifact@v4.1.7
       with:
         name: package-${{ github.sha }}
         path: conda-bld