Update populate script to overwrite location when changes come from sources.csv

[emmambd]

Describe the problem

Use case: https://mobilitydatabase.org/feeds/mdb-1824

• No automated location has ever been extracted from this feed, because the GTFS files are in a subfolder
• A contributor requested the location from the catalogs be updated from Izmit to Izmir
• The change was made on the catalogs, but the populate script doesn't actually track changes

Proposed solution

Update the populate script to

• Check location on latest dataset
• if location is set don't overwrite with sources.csv location
• otherwise overwrite

currently the script only checks if location is set on the feed and don't retrieve datasets

Alternatives you've considered

No response

Additional context

No response