Check if composer.lock file exist in composer-lint job
Problem/Motivation
In some special customised setups, the composer.lock file may not be present in the "modules/custom/..." folder, so the "composer-lint" job fails.
Steps to reproduce
https://git.drupalcode.org/issue/automatic_updates-3452870/-/jobs/1795280
Proposed resolution
Check if the file exist before renaming it.
Edited by drupalbot