Use forked setup-node action

See actions/setup-node#439; this works around Actions failures due to
this repo (properly!) using npm-shrinkwrap.json.

See https://github.com/strugee/password-requirements-dataset/runs/5487779652?check_suite_focus=true

.github/workflows/node.js.yml

@@ -21,7 +21,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v2
+      uses: strugee/setup-node@shrinkwrap-support
       with:
         node-version: ${{ matrix.node-version }}
         cache: 'npm'