Update ARC quickstart auth guidance

Author: suzunn

content/actions/tutorials/use-actions-runner-controller/get-started.md

@@ -45,7 +45,7 @@ In order to use ARC, ensure you have the following.
 
     For additional Helm configuration options, see [`values.yaml`](https://github.com/actions/actions-runner-controller/blob/master/charts/gha-runner-scale-set-controller/values.yaml) in the ARC documentation.
 
-1. To enable ARC to authenticate to {% data variables.product.company_short %}, generate a {% data variables.product.pat_v1 %}. For more information, see [AUTOTITLE](/actions/hosting-your-own-runners/managing-self-hosted-runners-with-actions-runner-controller/authenticating-to-the-github-api#deploying-using-personal-access-token-classic-authentication).
+1. To enable ARC to authenticate to {% data variables.product.company_short %}, choose an authentication method for your runner scale set. If you are registering runners at the repository or organization level, we recommend authenticating with a {% data variables.product.prodname_github_app %}. Enterprise-level runners require {% data variables.product.pat_v1 %} authentication. For more information, see [AUTOTITLE](/actions/hosting-your-own-runners/managing-self-hosted-runners-with-actions-runner-controller/authenticating-to-the-github-api).
 
 ## Configuring a runner scale set
 
@@ -56,6 +56,7 @@ In order to use ARC, ensure you have the following.
     * Update the `INSTALLATION_NAME` value carefully. You will use the installation name as the value of `runs-on` in your workflows. For more information, see [AUTOTITLE](/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idruns-on).
     * Update the `NAMESPACE` value to the location you want the runner pods to be created.
     * Set `GITHUB_CONFIG_URL` to the URL of your repository, organization, or enterprise. This is the entity that the runners will belong to.
+    * This example uses a {% data variables.product.pat_generic %} to keep the initial setup short. For repository or organization runner scale sets, use a {% data variables.product.prodname_github_app %} in production environments when possible.
     {% ifversion fpt %}
     * Set `GITHUB_PAT` to a {% data variables.product.company_short %} {% data variables.product.pat_generic %} with the `repo` and `admin:org` scopes for repository and organization runners.
     {% else %}