Use setup-node action to setup nodejs runtime

.github/workflows/run-tests.yaml

@@ -50,8 +50,10 @@ jobs:
           psql --host localhost --port ${{ job.services.postgres.ports[5432] }} --user postgres --password -c "CREATE DATABASE omnivore_test;"
         env:
           PGPASSWORD: postgres
-      - name: Setup nodejs 14.18
-        run: source ~/.nvm/nvm.sh && nvm install 14.18 && nvm use 14.18 && npm install -g yarn
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v2
+        with:
+          node-version: 14.18
       - name: Get yarn cache directory path
         id: yarn-cache-dir-path
         run: echo "::set-output name=dir::$(source ~/.nvm/nvm.sh && yarn cache dir)"