Convert a 2-character USA location code to a 2-letter USA location abbreviation.
Source:R/recode_locations.R
us_loc_code_to_abbr.Rd
Given a vector of US location
codes (legacy FIPS code for states and territories,
US
for the US, the schema typically used in forecast
hubs), return the corresponding state/territory
two-letter USPS short names (e.g. MA, TX, PR).