Update 8398a7/action-slack action to v3.19.0#981

renovate[bot] wants to merge 1 commit intomainnginx/nginx-asg-sync:mainfrom

renovate/8398a7-action-slack-3.xnginx/nginx-asg-sync:renovate/8398a7-action-slack-3.xCopy head branch name to clipboard