build(deps): bump actions/download-artifact from 4 to 8

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 8.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v8)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/test.yml

@@ -90,7 +90,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: ⬇️ Download coverage data
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
 
       - name: 🏗 Set up Python 3.12
         id: setup-python