After a MR is merged in a 'bsp' or 'tools' group repository all MRs
of that group are being retriggered in order to avoid issues in
successive MR integrations. This retrigger was acting on retriggering
 all opened MRs, so this change introduces:
 * Check on repository if INTEGRATION variable is defined, otherwise
skip the project MRs.
 * Check on the target branch of the final integration MR and triggers
 only pipelines on MRs affecting the same branch.
 * Cleanup the print statements for better job readability.