Converts incoming SystemSaveData that has a version below the
current version number listed in package.json.
Note that no transforms act on the data if its version matches
the current version or if there are no migrations made between its version up
to the current version.
Converts incoming
SystemSaveDatathat has a version below the current version number listed inpackage.json.Note that no transforms act on the data if its version matches the current version or if there are no migrations made between its version up to the current version.