Use Github Actions to make big shiny green merge button on Github merge to gitea

[robe]

I'm thinking it should be possible on Github to use Github actions to when one of us clicks the "Merge" big shiny merge button, it does a merge on gitea instead.

I think this will release some pain points people have.

Still looking at some examples, but all I've reviewed so far do the opposite - have Github merge - merge to a remote repo.