chore(deps): bump actions/download-artifact from 4 to 8 (#3767)

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 8.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](https://github.com/actions/download-artifact/compare/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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/backend-tests.yaml

@@ -130,13 +130,13 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Download PR coverage
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: backend-coverage-pr
           path: src/backend/coverage
 
       - name: Download base coverage
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: backend-coverage-base
           path: coverage-base

.github/workflows/puterjs-tests.yaml

@@ -173,7 +173,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Download PR coverage
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: puterjs-coverage-pr
           path: src/puter-js/coverage
@@ -183,7 +183,7 @@ jobs:
       - name: Download base coverage
         id: base-coverage
         continue-on-error: true
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: puterjs-coverage-base
           path: coverage-base