We're simplifying and improving the way code is pulled via our new GitHub integration. Using this integration, we will automatically generate GitHub tokens and use those instead of SSH keys where appropriate. This will provide better granularity for GitHub repository permissions.
For all repositories that have not been granted access through the integration (including those not on GitHub), there is no change in behaviour, and we will continue to use the SSH key as before.
This will be rolled out incrementally to all customers with the GitHub integration.
For more information, please visit our help page on pulling source code.