Warning about missing culture information in container image

[eliaspr]

Warning at the end seems weird and is potentially caused by missing dependencies in new alpine-based container image

info: Turnierplan.App.DatabaseMigrator[0]
      An initial user was created: You can log in using "admin" and the password "****" (set by environment variable). This is NOT recommended in a production environment!
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: http://[::]:8080
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /app
warn: Turnierplan.Localization.LocalizationProvider[0]
      Could not find CultureInfo for language code 'de'. Falling back to 'InvariantCulture'.