test_wrapper: make errors more informative

4 jobs for 1.0
Status Job ID Name Coverage
  External
passed ERP5.StandaloneDeploymentScriptTest-Debian.Buster.Master

passed SlapOS-Master.StandaloneDeploymentScriptTest-Debian.Buster

failed SlapOS.Theia.ResilienceTest-Master

failed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master