Populate the "import" properties defined for translator

With TEIID-2904, Teiid 8.7 will contain a facility to retrieve the import properties for a translator that are used to customize the metadata import process through Admin API.

Teiid Connection importer needs currently is designed to add ad-hoc import properties, and this can be enhanced to populate with this dynamic list, so that user does not have to search through documents for these import properties.