Switched to Node.js container in Action

no issue

- using the setup-node action is currently failing because of an
  upstream issue - nodejs/node#32683
- this commit switches to using a Docker container

.github/workflows/test.yml

@@ -8,6 +8,7 @@ on:
 jobs:
   test:
     runs-on: ubuntu-latest
+    container: node:10
     if: github.event_name == 'push' || (github.event_name == 'pull_request' && !startsWith(github.head_ref, 'renovate/'))
     strategy:
       matrix:
@@ -19,9 +20,6 @@ jobs:
       CI: true
     steps:
       - uses: actions/checkout@v2
-      - uses: actions/setup-node@v1
-        with:
-          node-version: 10
       - run: yarn
       - run: yarn lint:js
       - run: yarn test