GeoIp2InfoRetriever has implicitly been the reader for "free" tier databases, ie. GeoLite2. We should be explicit about this and remove faux-support for the info we know we won't have access to in the GeoLite2 databases (eg. proxy information).
AC
- Rename GeoIp2InfoRetriever to GeoLite2InfoRetriever and make all necessary downstream changes where it's called
- Audit and clean up functions that will never return anything besides a null/null-like value (eg. proxy information) and make a note of its lack of support*
- Document in https://www.mediawiki.org/wiki/Extension:IPInfo that GeoLite2InfoRetriever only supports GeoLite2-like databases (I can't immediately find a list from maxmind but a list would certainly be helpful, even if we have to make it ourselves)
*For now. An update could come with T293907: Be more specific about falsy values in IP Info api [1H] that would change this AC to support whatever the decision from that ticket is.