chore(deps): bump actions/download-artifact from 4 to 6

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...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/test.yml

@@ -64,7 +64,7 @@ jobs:
           node-version: "22.18.0"
 
       - name: Download all coverage artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           pattern: coverage-*
           path: coverage-artifacts/
@@ -144,7 +144,7 @@ jobs:
         run: cd src/view && pnpm install
 
       - name: Download all blob reports
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           pattern: blob-report-*
           path: all-blob-reports/