Always use bundle exec

Author: hsbt

.github/workflows/test.yml

@@ -41,10 +41,9 @@ jobs:
       id: bundle
       run: |
         bundle install
-        echo "exec=bundle exec" >> $GITHUB_OUTPUT
       if: "matrix.ruby <= '2.1'"
     - name: Run test
-      run: ${{steps.bundle.outputs.exec}} rake test
+      run: bundle exec rake test
     - id: build
       run: |
         rake build