stack/slapos: Change the version number of pytest-runner from 5.2.0 to 5.2

Use the exact version number displayed on the pypi index, because our shacache system is based on the URL which contains a package version number.
19 jobs for feat/slapos_core_python3
Status Job ID Name Coverage
  External
passed Cloudooo.UnitTest-Master

00:18:19

passed SlapOS.Eggs.UnitTest-Master.Python2

00:13:57

passed SlapOS.Eggs.UnitTest-Master.Python3

00:24:15

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:55

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:40:15

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

06:13:57

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

06:00:52

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:50:15

passed SlapOS.Eggs.UnitTest-Master.Python2

00:26:00

passed SlapOS.Eggs.UnitTest-Master.Python2

00:13:36

passed SlapOS.Eggs.UnitTest-Master.Python3

00:14:06

passed SlapOS.Eggs.UnitTest-Master.Python3

00:13:21

passed SlapOS.SlapRunner.ResilienceTest-Master

00:24:10

passed SlapOS.SlapRunner.ResilienceTest-Master

00:22:20

passed SlapOS.SlapRunner.ResilienceTest-Master

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:42:32

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:50:42

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:29:07