enable automatic publish after dependabot

[arznaar]

I've tried several approaches:

1. publish on push to develop
   it looks most as the most natural, but push event isn't triggered after dependabot pr was merged if this automerge was set from action
2. separate action on PR event "closed" that, if status is "merged", triggers publish event
   this way we rely on the fact that we never actually push to develop directly and always merge PRs there. But triggering other action via scripts didn't really work. Nothing in the logs. Looks like it can't find the actor who did this and skipped it. When I've triggered it manually - all worked.
3. trigger publish of PR "closed" and publish merge commit.
   this one may have some quirks if there are several PRs opened simultaneous, but even this didn't work and never triggered PRs on "merged" status. It triggered once dependabot closed PR as unneeded, but not on merge. Strange

• try logging all PR events, it's a bit strange that in (2) actions were triggered on "closed", but for (3) they aren't. Is it due to target branch?
• the worse case would be adding my personal token to trigger action with it for case (2), but let's postpone this