text: Title: HTTP Error 429: too many requests causes tests to fail
  Body: Occasionally, the test suite can fail when it fetches the data from the same URL too frequently, we should replace the URL link with local versions of the cars.csv if possible. In addition, any remote fetches of the data should catch the HTTP 429 error and add a sleeping timer to ensure that the test doesn't fail when the query rate is too high.
  We could also look into dataframe reuse opportunities across tests so that the dataframe doesn't need to be reloaded every single time.
  ![image](https://user-images.githubusercontent.com/5554675/94279144-4a8df180-ff7e-11ea-86c5-e4e803a875be.png)
  