title: Kubernetes Helm: not a valid chart repository
body: <p>According to <a href="https://cert-manager.io/docs/installation/kubernetes/" rel="nofollow noreferrer">cert-manager installation docs</a> jetstack repository should be added:</p>
  <blockquote>
  <p>$ helm repo add jetstack <a href="https://charts.jetstack.io" rel="nofollow noreferrer">https://charts.jetstack.io</a></p>
  </blockquote>
  <p>It gives error message:</p>
  <blockquote>
  <p>Error: looks like &quot;https://charts.jetstack.io&quot; is not a valid chart repository or cannot be reached: error unmarshaling JSON: while decoding JSON: json: unknown field &quot;serverInfo&quot;</p>
  </blockquote>
  <p>What are the ways to fix the issue?</p>