I have the Github Integration already installed, but Autofix is telling me that I do not.

This prompt will display on issues where code mappings have not been set up. You will be able to tell if code mappings are not set up based on the existence of the “Set up code mapping” button in the stack trace frame. You can click the button to set up code mappings for this issue, or visit our docs on the subject here, to learn how to manually set them up.