RFR: 1948: User not getting push access to backport branch

[Erik Joelsson]

When a user creates a backport PR using the /backport command, they are supposed to get push access to the branch in the fork repository. On GitHub, this has stopped working (assuming it ever worked). Experimentation shows that for a user to be eligible for listing in a branch protection rule, that user must first have push access in the repository. Just having a pending invite is not enough. When a user issues the /backport command, an invite is automatically sent to become a collaborator with push access in the repository, but the user has to accept it before it comes into effect.

Given this, I don't see a way to consistently provide branch level push access restrictions for the fork repositories. But instead of removing the feature completely, we can apply it when possible. The first /backport by a user will not get exclusive push access, but if the user accepts the invite before the next time, then from then on, any new backport branches will be protected. Not sure if this is worth it, but since we have the functionality, we may as well apply it when possible.

-------------

Commit messages:
 - SKARA-1948

Changes: https://git.openjdk.org/skara/pull/1532/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1532&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-1948
  Stats: 17 lines in 2 files changed: 16 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/skara/pull/1532.diff
  Fetch: git fetch https://git.openjdk.org/skara.git pull/1532/head:pull/1532

PR: https://git.openjdk.org/skara/pull/1532