ci: bump the actions group with 2 updates

Bumps the actions group with 2 updates: [actions/checkout](https://github.com/actions/checkout) and [actions/download-artifact](https://github.com/actions/download-artifact).


Updates `actions/checkout` from 4 to 5
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v4...v5)

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

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

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

.github/workflows/emscripten.yml

@@ -13,7 +13,7 @@ jobs:
     if: github.actor == 'dependabot[bot]'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           ref: ${{ github.event.pull_request.head.sha }}