Add GitHub integration for civicrm-dev-docs to https://chat.civicrm.org/civicrm/channels/documentation
Update config file for mattermost-github integration to add an integration of https://github.com/civicrm/civicrm-dev-docs to https://chat.civicrm.org/civicrm/channels/documentation , per this - https://github.com/softdevteam/mattermost-github-integration#usage