Update testmodulowy.yml to newest LTS version

.github/workflows/testmodulowy.yml

@@ -12,10 +12,17 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [14.x, 16.x, 18.x]
+        node-version: [18.x]
 
     steps:
     - uses: actions/checkout@v3
+    - name: Cache node modules
+      uses: actions/cache@v2
+      with:
+        path: ~/.npm
+        key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
+        restore-keys: |
+          ${{ runner.os }}-node-
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v3
       with: