This class contains shared properties across the two types of configuration builders. Abstracting this allows for minimal rewiring by the compiler plugin since build is available to both builders.
The property functions in this builder return the type of the builder itself, represented by S. This is due to library-base not having visibility over library-sync and therefore all function return types have to be typecast as S.
Sets the schema version of the Realm. This must be equal to or higher than the schema version of the existing Realm file, if any. If the schema version is higher than the already existing Realm, a migration is needed.