Bump actions/download-artifact from 4 to 6 (#59)

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v6)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/publish.yml

@@ -115,7 +115,7 @@ jobs:
       id-token: write  # IMPORTANT: mandatory for trusted publishing
     steps:
     - name: Download all the dists
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v6
       with:
         name: python-package-distributions
         path: dist/
@@ -152,7 +152,7 @@ jobs:
           echo "prerelease=false" >> $GITHUB_OUTPUT
         fi
     - name: Download all the dists
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v6
       with:
         name: python-package-distributions
         path: dist/