build(deps): bump actions/download-artifact from 3 to 4

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 3 to 4.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v3...v4)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/pythonpackage.yml

@@ -95,7 +95,7 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Fetch packages
       if: matrix.install == 'sdist' || matrix.install == 'wheel'
-      uses: actions/download-artifact@v3
+      uses: actions/download-artifact@v4
       with:
         name: dist
         path: dist/