refactor: use covidcast state_census.csv directly rather than package

Author: dshemetov

data-raw/state_census.R

@@ -1,7 +1,7 @@
 library(dplyr)
 library(covidcast)
 
-state_census <- covidcast::state_census %>%
+state_census <- read_csv("https://github.com/cmu-delphi/covidcast/raw/c89e4d295550ba1540d64d2cc991badf63ad04e5/Python-packages/covidcast-py/covidcast/geo_mappings/state_census.csv") %>% # nolint: line_length_linter
   select(STATE, NAME, POPESTIMATE2019, ABBR) %>%
   rename(abbr = ABBR, name = NAME, pop = POPESTIMATE2019, fips = STATE) %>%
   # Left-pad FIPS codes with zeroes to 2 digits, and convert to character