Idea from @rdicosmo:
As an alternative to the "save to SWH" github action, we could provide an API endpoint that can be called by forges (github, gitlab, gitea/gogs, ...) to notify us of a push or new tag.
- less wasteful on the forge's side (it's just an HTTPS request, not a container with its own nodejs process, ...)
- easier to setup for users (a few clicks in the forge's UI)
- more secure (no need to trust the action's author)
- works for all forges
- might allow us to extract information from the webhook payload, in the future