testing: don't reset PYTHONPATH

we no longer use python setup.py test
13 jobs for feat/no-PYTHONPATH in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.Eggs.UnitTest-Jerome.Python2

00:21:02

passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:10:29

passed SlapOS.SoftwareReleases.IntegrationTest-Jerome-Python3

04:39:11

passed SlapOS.SoftwareReleases.IntegrationTest-Jerome-WIP

14:48:58

passed SlapOS.Eggs.UnitTest-Jerome.Python2

00:09:40

passed SlapOS.Eggs.UnitTest-Jerome.Python2

00:17:29

passed SlapOS.Eggs.UnitTest-Jerome.Python2

00:14:35

failed SlapOS.Eggs.UnitTest-Jerome.Python2

00:16:51

passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:13:48

passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:15:31

passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:13:41

passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:39:43

canceled SlapOS.SoftwareReleases.IntegrationTest-Jerome-WIP

10:53:31