erp5_core: continue pylint test even if it raises an exception.

5 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

01:26:19

failed ERP5.UnitTest-Master

02:08:03

passed SlapOS.Eggs.UnitTest-Master.Python2

00:19:13

passed SlapOS.Eggs.UnitTest-Master.Python3

00:29:39

failed Wendelin.UnitTest-Master

00:56:54