ci(tools): update dependency ruby to v4 (#58)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/testing.yml

@@ -23,7 +23,7 @@ jobs:
       - name: Setup ruby
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 3.4.8
+          ruby-version: 4.0.0
           bundler-cache: true
 
       - name: Run rubocop