ROUT: update jsonp-p to use fetch

[anselmbradford]

https://github.com/cfpb/consumerfinance.gov/blob/main/cfgov/unprocessed/apps/rural-or-underserved-tool/js/call-census.js#L1 and https://github.com/cfpb/consumerfinance.gov/blob/main/cfgov/unprocessed/apps/rural-or-underserved-tool/js/call-tiger.js#L1 uses a 6 year old package jsonp-p https://www.npmjs.com/package/jsonp-p

I would imagine this could be updated to use a native fetch call and the dependency could be tossed.

[anselmbradford]

Investigated this and there is a problem. The census API we're using to geocode does not support CORS, which changing this to a fetch call requires.

https://stackoverflow.com/questions/51017702/enable-cors-in-fetch-api has some good background on CORS in fetch in general, and https://medium.com/@wherewhat/using-census-bureau-apis-client-side-in-javascript-ce6c1847c533 shows hitting the census API via a proxy.