Unclear target class in `dandischema.metadata.migrate()`

[candleindark]

I noticed that dandischema.metadata.migrate() is not only used to migrate Dandiset objects but PublishedDandiset objects as well ( see https://github.com/dandi/dandi-archive/blob/master/dandiapi/api/management/commands/migrate_published_version_metadata.py). However, it seems that dandischema.metadata.migrate() is hardcoded to handle only Dandiset objects, as indicated in the following lines:

dandi-schema/dandischema/metadata.py

Line 435 in f0be592

_validate_obj_json(obj, _get_jsonschema_validator(obj_ver, "Dandiset"))

dandi-schema/dandischema/metadata.py

Line 460 in f0be592

obj_migrated["schemaKey"] = "Dandiset"

That is the expected metadata instance input of the migrate() function, only instances of Dandiset, not including instances of PublishedDandiset, or instances of Dandiset and its subclass PublishedDandiset.

This problem would be more of an issue if #266 is to put in place to enforce more strict validation.