topic sort criteria do not get added to the json on export

[spereverde]

When testing the topic to collection migration we noticed to sort_on and sort_reversedmetadata seems to not get migrated.
it seems like it is just forgotten to add that to the metadata.

With a quick look it seems that it might be fixed by replacing

    self._collection_sort_reversed = criterion.getReversed()
    self._collection_sort_on = criterion.Field()

with

topic_metadata["sort_reversed"] = criterion.getReversed()
topic_metadata["sort_on"]  = criterion.Field()

in this file:
https://github.com/collective/collective.exportimport/blob/main/src/collective/exportimport/serializer.py#L341

or adding it below the
topic_metadata["query"] = json_compatible(formquery) on line 361

related: https://github.com/plone/plone.app.contenttypes/blob/1.1.1/plone/app/contenttypes/migration/topics.py#L505

Let me know if this seems correct to you, then we will make a PR