.github: Specify the download artifact for the distribution

Omitting the artifact name changes the behavior, it will download all
artifacts and create subdirectories for each.

Signed-off-by: Pieter De Gendt <pieter.degendt@basalte.be>

.github/workflows/release.yml

@@ -30,6 +30,7 @@ jobs:
     - name: Download build artifacts
       uses: actions/download-artifact@v4
       with:
+        name: python-package-distributions
         path: dist/
 
     # The assets can be attached to an existing release, if a matching tag is found