Bump actions/download-artifact from 4 to 5 (TGSAI#692)

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 5.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v5)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/tests.yml

@@ -115,7 +115,7 @@ jobs:
           nox --version
 
       - name: Download coverage data
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           pattern: coverage-data-*
           merge-multiple: true