I'm not generally against having an AppImage repository under the Geany organisation, I just don't see the benefits and why it's worth the efforts to migrate the already existing repository.
I guess there will be the "official" argument but does it really matter that much? Despite the general perception, technically it makes no difference and might be even a wrong suggestion to the user. Why would be an AppImage repository in the Geany repository be more official than a repository elsewhere? It's still someone else who maintains it and there is not more or less QA, I think.
Apart from that, I would recommend to *not* build new images on each push to PRs or master branch. This seems like a huge waste of resources. Additionally, when Travis CI is used, you'll probably running out of free credits quickly. Migrating to Github Actions could be a solution, I'm going to propose this also for the Geany repositories.