The list of authentication backends supported by Gerrit does not include GitHub and it cannot be used out of the box, as it does not support OpenID authentication. However, a GitHub plugin for Gerrit has been recently released in order to fill the gaps and allow a seamless integration.
GitHub implements OAuth 2.0 for allowing external applications, such as Gerrit, to integrate using a three-step browser-based authentication. Using this scheme, a user can leverage their existing GitHub account without the need to provision and manage a separate one in Gerrit. Additionally, the Gerrit instance will be able to self-provision the SSH public keys needed for pushing changes for review.
In order for us to use GitHub OAuth authentication ...