Check if SDG exists in Nautilus DB before adding record to the eHB

[seg1129]

In current state ehb-datasources does not check if a SDG name exists in nautilus before adding it to the eHB.

the following function needs to be updated to check if SDG name exists in nautilus before checking if the record already exists in the eHB

ehb-datasources/ehb_datasources/drivers/nautilus/driver.py

Line 349 in d38c2ae

def process_new_record_form(self, request, record_id_prefix,