Added extremely simple tests for future refactoring.

.github/workflows/solve.yaml

@@ -15,6 +15,8 @@ jobs:
           distribution: 'corretto' # See 'Supported distributions' for available options
           java-version: '21'
       - uses: https://github.com/fwilhe2/setup-kotlin@main
+      - name: Run tests
+        run: ./simpletest.sh
       - name: Solutions
         run: |
           set -e