Add some more generated metadata files

#1915 adds metadata generation (with stored expected results). We should expand the collection in two directions:

• The current metadata is basically all with default values: Add More variation on the metadata (different key types, delegations, targets, etc)
• Include actual repositories (that are confirmed to work as repositories), possibly with several versions of the same repository: Note that we should be careful not to duplicate the code in RepositorySimulator based updater tests: possibly we could just make RepositorySimulator generated data reproducible and store the results of the RepositorySimulator runs (see the --dump option for related tests)

I'll assign to myself: I'll probably handle the first item and file a new issue on the second but let's see...

Inizia leggendo #1915 e i relativi risultati attesi dei metadati memorizzati per comprendere la raccolta generata attuale. Poi esamina RepositorySimulator e l’opzione --dump nei test correlati, poiché, come suggerisce l’issue, potrebbero fornire dati di repository riproducibili. Il lavoro è completato quando si amplia la variazione dei metadati e si considerano esempi confermati di repository senza duplicare i dati di updater-test.