An API key is required to use the functions in caRecall and query the
Vehicle Recalls Database. The key can be acquired at
https://tc.api.canada.ca/en/detail?api=VRDB.
The key can be set in the environment using
Sys.setenv(VRD_API = 'your_API_key_here'). Alternatively, instead of
setting the API key in the environment, the key can be passed into the
functions as an argument.