I need to find the solution of the exact situation, that has been described in the question.
I only have a feature Branch ID, for which I need to get the Pull Request ID or Url, on GitBash(2.20.1) or Terminal without calling Github API..
I have already tried this, but it doesn't work for every Branch or always, don't know why.
git ls-remote origin 'pull/*/head' | grep -F -f <(git rev-parse HEAD) | awk -F'/' '{print $3}'