feat(ci): add test step to GitHub Actions workflow

This commit adds a new step to the GitHub Actions CI workflow to run
the test suite. This ensures that all tests pass before any changes
are merged into the main branch.

Author: ryoppippi

.github/workflows/ci.yaml

@@ -23,3 +23,5 @@ jobs:
         run: pnpm typecheck
       - name: Run lint
         run: pnpm lint
+      - name: Run test
+        run: pnpm test