Support current variables for air quality

[JosiahParry]

I tried using this command to get some information about the air quality at my location. However this doesn't work because the pollen data is not hourly so I get NA values here.

variables <- c("alder_pollen", "birch_pollen", "grass_pollen", "mugwort_pollen", "olive_pollen", "ragweed_pollen", "dust", "us_aqi")

air_quality(
  c(ip_info$latitude, ip_info$longitude), 
  hourly = variables
) 

Having validation of input variables would be great. Secondly it would be great if you could support the current as well