Bump dawidd6/action-download-artifact from 2 to 6 in /.github/workflows

Bumps [dawidd6/action-download-artifact](https://github.com/dawidd6/action-download-artifact) from 2 to 6.
- [Release notes](https://github.com/dawidd6/action-download-artifact/releases)
- [Commits](dawidd6/action-download-artifact@v2...v6)

---
updated-dependencies:
- dependency-name: dawidd6/action-download-artifact
  dependency-type: direct:production
...

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

.github/workflows/publish.yml

@@ -18,7 +18,7 @@ jobs:
     # It also restores the files timestamps.
 
     - name: Download sdist and wheel from commit ${{ github.sha }}
-      uses: dawidd6/action-download-artifact@v2
+      uses: dawidd6/action-download-artifact@v6
       with:
         workflow: workflow.yml
         workflow_conclusion: success
@@ -27,7 +27,7 @@ jobs:
         path: dist
 
     - name: Download sdist from commit ${{ github.sha }}
-      uses: dawidd6/action-download-artifact@v2
+      uses: dawidd6/action-download-artifact@v6
       with:
         workflow: workflow.yml
         workflow_conclusion: success