job to delete trashed ciphers nightly (#1243)

* job to delete trashed items nightly

* remove script from migration project file

* admin setting for controlling trash deleting dates

src/Core/Repositories/ICipherRepository.cs

@@ -36,5 +36,6 @@ namespace Bit.Core.Repositories
         Task SoftDeleteAsync(IEnumerable<Guid> ids, Guid userId);
         Task SoftDeleteByIdsOrganizationIdAsync(IEnumerable<Guid> ids, Guid organizationId);
         Task<DateTime> RestoreAsync(IEnumerable<Guid> ids, Guid userId);
+        Task DeleteDeletedAsync(DateTime deletedDateBefore);
     }
 }