stack/slapos: version up passlib 1.7.4

should fix crypt issues with python 3.9
Status Job ID Name Coverage
  External
running Cloudooo.UnitTest-Master

12407:55:25

running ERP5.StandaloneDeploymentScriptTest-Debian.Buster.Master

12407:55:07

running SlapOS.Eggs.UnitTest-Jerome.Python2

12407:54:47

running SlapOS.Eggs.UnitTest-Jerome.Python3

12407:54:42

running SlapOS.SlapRunner.ResilienceTest-Master

12407:54:53

running SlapOS.SoftwareReleases.IntegrationTest-Master

12407:55:17

running Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

12407:55:38