slapos_erp5: Drop fetch date from activities

   Use recently added API to speed up the rendering.
7 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
failed SlapOS-Master.UnitTest-Master

02:05:18

failed SlapOS.Eggs.UnitTest-Master.Python2

00:27:07

failed SlapOS.Eggs.UnitTest-Master.Python3

00:41:29

failed SlapOS-Master.UnitTest-Master

02:01:59

passed SlapOS.Eggs.UnitTest-Master.Python2

00:38:53

failed SlapOS.Eggs.UnitTest-Master.Python2

00:27:44

failed SlapOS.Eggs.UnitTest-Master.Python3

00:48:34