software/jupyter: Fix instance template download

6 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.SlapRunner.ResilienceTest-Master

00:24:29

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

00:09:58

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

08:33:47

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

06:51:18

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

06:21:38

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

04:54:50