stack/erp5: Prepare for trusted frontend SSL Auth

Remote-User header shall be trusted if comes from trusted frontend.
Status Job ID Name Coverage
  External
failed SlapOS.SoftwareReleases.IntegrationTest-luke/feature/erp5-prepare-for-trusted-frontend

47:22:56

running SlapOS.SoftwareReleases.IntegrationTest-luke/feature/erp5-prepare-for-trusted-frontend

27261:04:34

failed SlapOS.SoftwareReleases.IntegrationTest-luke/feature/erp5-prepare-for-trusted-frontend

19:43:57