software/theia: Fix EPR5 resiliency test

Now that `slapos request` understands `json-in-xml` serialisation and
automatically unwraps the instance connexion parameters when printing
them, we need to adapt how the ERP5 test parses that output.
9 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.Eggs.UnitTest-Master.Python2

00:15:06

passed SlapOS.Eggs.UnitTest-Master.Python3

00:20:55

passed SlapOS.SlapRunner.ResilienceTest-Master

00:22:14

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

08:40:22

passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

07:31:27

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

06:53:42

passed SlapOS.Eggs.UnitTest-Master.Python2

00:09:36

passed SlapOS.Eggs.UnitTest-Master.Python3

00:20:10

passed SlapOS.SlapRunner.ResilienceTest-Master

00:22:45