ci: rerun issue check on PR edit

Re-run issue check when a PR is updated, i.e. when someone adds
'Fixes...` to the PR body.

This is mostly for release branches and has no effect on main branch.

Also, add concurrency check in the workflow.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
(cherry picked from commit 4077249c)