Investigate migrating to using the new Dockstore GitHub App

[cwhelan]

Dockstore has a new workflow for GitHub workflow integration using a GitHub App which they recommend migrating to:

https://docs.dockstore.org/en/stable/getting-started/github-apps/migrating-workflows-to-github-apps.html

The main advantage of switching over to this that I can see would be that updates to the repo would be automatically picked up by docstore -- currently after a release someone has to login to Dockstore and hit the "refresh" button to get the release to show in Dockstore and Terra.