This explains how to automatically rebuild documentation on ReadtheDocs
every time a pull request is merged into its corresponding GitHub repo.
Webhooks and services can be enabled in GitHub repo settings to allow third
party services such as ReadTheDocs. The ReadTheDocs service rebuilds the
project documentation whenever a pull request is merged into the GitHub repo.
Each GitHub repo has a Settings tab at the far right of the repo menubar. Navigate to Settings and then the Webhooks & services submenu tab.
Select Add service and enter ReadTheDocs in the Available Services input box.
The Services/Add ReadTheDocs window will open. Press the green Add service button to activate the ReadTheDocs service.
The ReadTheDocs service is added successfully. The service will take effect on the next merged pull request to the project repo.