multi-version node workflow

.github/workflows/run-tests.yaml

@@ -9,6 +9,10 @@ on:
       - main
 
 jobs:
+  matrix-strategy:
+    strategy: 
+      matrix: 
+        version: [18.18, 20.18]
   test-runner:
     name: test runner
     runs-on: ubuntu-latest
@@ -19,6 +23,8 @@ jobs:
         uses: actions/checkout@v4
       - name: setup node
         uses: actions/setup-node@v4
+        with: 
+          node-version: ${{ matrix.version }}
       - name: initialize deps
         run: npm install
       - name: run tests