Release 21.8.4

Bump actions/setup-node from 2.3.0 to 2.3.1

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 2.3.0 to 2.3.1.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](https://github.com/actions/setup-node/compare/v2.3.0...v2.3.1)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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