Bump ruby/setup-ruby from 1.78.0 to 1.79.0 (#18688)

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.78.0 to 1.79.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Commits](https://github.com/ruby/setup-ruby/compare/v1.78.0...v1.79.0)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/test.yml

@@ -57,7 +57,7 @@ jobs:
       - name: Check out files from GitHub
         uses: actions/checkout@v2.3.4
       - name: Setting up Ruby 2.6
-        uses: ruby/setup-ruby@v1.78.0
+        uses: ruby/setup-ruby@v1.79.0
         with:
           ruby-version: 2.6
       - name: Setup Ruby Gems cache