Bump actions/download-artifact from 5 to 6

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v5...v6)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -46,7 +46,7 @@ jobs:
           # Sonar analysis needs the full history for features like automatic assignment of bugs. If the following step
           # is not included the project will show a warning about incomplete information.
           fetch-depth: 0
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v6
         with:
           name: code-coverage-ubuntu-latest-22.x
           path: coverage/