feat(conversion) : add postgres_fdw extension in conversion scripts

related #7 (closed)

First tests of processing integration indicates that the postgres_fdw extension doesn't exist in VECTOR-DB stored data : https://geoplateforme-sandbox-oslandia-gpf-gitlab.dev.gpf-tech.ign.fr/chains/test/-/jobs/38

Conversion script are updated for postgres_fdw extension creation.