title: Create a zip archive via Google Cloud Build step to publish it as an artifact
body: <p>I'm building a modern WP theme via GCB, and I need a final artifact, a ZIP package. Being new to the GCBб I didn't manage to solve it on my own, but it sounds so obvious</p>
  
  <p>Anyway, here's my final build step</p>
  
  <pre><code>- name: 'gcr.io/cloud-builders/yarn'
    args: ['build:production']
  </code></pre>
  
  <p>I need to create a ZIP archive of the yarn output, recursively including all folder except node_modules, and publish the ZIP as an artifact (this part is clear, and I already got the storage bucket working).</p>
  
  <p>Appreciate the help!</p>