Add npm ci to integration test

.github/workflows/integration.yml

@@ -39,6 +39,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
+      - uses: actions/cache@v1
+        with:
+          path: ~/.npm
+          key: ${{runner.os}}-npm-${{hashFiles('**/package-lock.json')}}
+          restore-keys: ${{runner.os}}-npm-
+      - uses: npm ci
       - id: output-set
         uses: ./
         with: