testcase: Snapshot more interesting files

supervisor configuration is interesting to inspect in, the same for runners
in run and service directories.

/reviewed-on !170
15 jobs for <span class="ref-name">feat/better_testcase_snapshots</span> in 0 seconds
Status Job ID Name Coverage
  External
failed SlapOS.Eggs.UnitTest-Master.Python2

00:15:18

failed SlapOS.Eggs.UnitTest-Master.Python3

00:15:46

failed SlapOS.Eggs.UnitTest-Master.Python2

00:16:25

failed SlapOS.Eggs.UnitTest-Master.Python2

00:14:48

failed SlapOS.Eggs.UnitTest-Master.Python2

00:21:27

failed SlapOS.Eggs.UnitTest-Master.Python2

00:23:35

failed SlapOS.Eggs.UnitTest-Master.Python2

00:21:23

failed SlapOS.Eggs.UnitTest-Master.Python2

00:14:57

failed SlapOS.Eggs.UnitTest-Master.Python2

00:15:13

failed SlapOS.Eggs.UnitTest-Master.Python3

00:16:19

failed SlapOS.Eggs.UnitTest-Master.Python3

00:15:01

failed SlapOS.Eggs.UnitTest-Master.Python3

00:18:39

failed SlapOS.Eggs.UnitTest-Master.Python3

00:11:38

failed SlapOS.Eggs.UnitTest-Master.Python3

00:15:23

failed SlapOS.Eggs.UnitTest-Master.Python3

00:16:21