Bump ruby/setup-ruby from 1.267.0 to 1.278.0 (#128)

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.267.0 to 1.278.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](ruby/setup-ruby@d5126b9...4c24fa5)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-version: 1.278.0
  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>

Author: dependabot[bot]

.github/workflows/rubocop.yml

@@ -15,7 +15,7 @@ jobs:
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@d5126b9b3579e429dd52e51e68624dda2e05be25
+        uses: ruby/setup-ruby@4c24fa5ec04b2e79eb40571b1cee2a0d2b705771
         with:
           ruby-version: .ruby-version
           bundler-cache: true

.github/workflows/tests.yml

@@ -18,7 +18,7 @@ jobs:
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8
 
       - name: Setup Ruby
-        uses: ruby/setup-ruby@d5126b9b3579e429dd52e51e68624dda2e05be25
+        uses: ruby/setup-ruby@4c24fa5ec04b2e79eb40571b1cee2a0d2b705771
         with:
           ruby-version: .ruby-version
           bundler-cache: true