OZG-5012 adjust admin app

...n-settings/src/lib/configuration/configuration.service.ts

...ontainer/organisationseinheit-container.component.spec.ts

...in-settings/src/lib/postfach/postfach-resource.service.ts

.../admin-settings/src/lib/postfach/postfach.service.spec.ts

...ent/libs/admin-settings/src/lib/user/user.service.spec.ts

...ibs/tech-shared/src/lib/resource/resource.service.spec.ts

...client/libs/tech-shared/src/lib/resource/resource.util.ts