title: Can't connect to my backend when running Cypress on Github Actions
body: <p>I have a React app that I'm testing with Cypress. I then have a separated backend running on Graphql-yoga. Everything works fine locally and testing with Cypress also works flawlessly.</p>
  <p>But now I'm trying to use Github Actions for the first time and I have created a job to get my backend, start it, get my frontend and run Cypress. I have a console log with 'Server running on port ...' on my server, and I'm seeing it when the job runs, but still Cypress isn't connecting to my backend and I have no clue why. All Cypress tests but one are failing. The only test that's not failing is one I've created just to make sure the backend isn't sending any response. I don't see any errors/warning related to it.</p>
  <p>Here's my workflow file:</p>
  <pre><code>name: CI
  
  # Controls when the action will run.
  on:
    # Triggers the workflow on push or pull request events but only for the master branch
    push:
      branches: [master]
    pull_request:
      branches: [master]
  
    # Allows you to run this workflow manually from the Actions tab
    workflow_dispatch:
  
  jobs:
    cypress:
      runs-on: ubuntu-latest
  
      steps:
        - name: Checkout backend repo
          uses: actions/checkout@v2
          with:
            repository: ****/****
            token: ${{ secrets.REPO_TOKEN }}
            path: backend
  
        - name: Set up Nodejs ${{ matrix.node-version }}
          uses: actions/setup-node@v1
          with:
            node-version: ${{ matrix.node-version }}
  
        - name: Install backend dependencies
          working-directory: ./backend
          run: npm install
  
        - name: Run backend
          working-directory: ./backend
          run: node server.js &amp;
          env:
            APP_SECRET: ${{ secrets.BE_APP_SECRET }}
            FIREBASE_SERVER_KEY: ${{ secrets.BE_FIREBASE_SERVER_KEY }}
            CLOUDINARY_SECRET: ${{ secrets.BE_CLOUDINARY_SECRET }}
            CLOUDINARY_KEY: ${{ secrets.BE_CLOUDINARY_KEY }}
            NODE_ENV: ${{ secrets.BE_NODE_ENV }}
            DATABASE_URL: ${{ secrets.BE_DATABASE_URL }}
  
        - name: Checkout frontend repository
          uses: actions/checkout@v2
  
        - name: Install dependencies
          run: npm install
  
        - name: Run Cypress tests
          uses: cypress-io/github-action@v2
          with:
            start: npm start
            wait-on: 'http://localhost:3000'
            config: baseUrl=http://localhost:3000
          env:
            REACT_APP_FIREBASE_API_KEY: ${{ secrets.REACT_APP_FIREBASE_API_KEY }}
            REACT_APP_NODE_ENV: test
  </code></pre>
  <p>Any ideas what might be the problem?
  Thanks in advance!</p>