fix tests

[mpadge]

initial submission of v0.2.0 fails on CRAN with

 > test_check("bikedata")
    adding: temp/RtmpoFHPNf/Divvy_Trips_sample/ (stored 0%)
    adding: temp/RtmpoFHPNf/Divvy_Trips_sample/Divvy_Stations.csv (deflated 69%)
    adding: temp/RtmpoFHPNf/Divvy_Trips_sample/Divvy_Trips_sample.csv (deflated 79%)
    adding: temp/RtmpoFHPNf/201701-hubway-tripdata.csv (deflated 81%)
    adding: temp/RtmpoFHPNf/201801_hubway_tripdata.csv (deflated 81%)
    adding: temp/RtmpoFHPNf/Nice_Ride_data_2012_season/ (stored 0%)
    adding: temp/RtmpoFHPNf/Nice_Ride_data_2012_season/Nice_Ride_2012-station_locations .csv (deflated 62%)
    adding: temp/RtmpoFHPNf/Nice_Ride_data_2012_season/Nice_Ride_trip_history_2012_season.csv (deflated 82%)
    adding: temp/RtmpoFHPNf/2017Q1-capitalbikeshare-tripdata-temp.csv (deflated 80%)
    adding: temp/RtmpoFHPNf/la_metro_gbfs_trips_Q1_2017.csv (deflated 85%)
    adding: temp/RtmpoFHPNf/201612-citibike-tripdata.csv (deflated 74%)
  -- 1. Error: write and store data (@test-store-data.R#44)  ---------------------
  No stations returned; please try again
  1: expect_silent(n <- store_bikedata(data_dir = tempdir(), bikedb = bikedb, quiet = TRUE)) at testthat/test-store-data.R:44
  2: quasi_capture(enquo(object), evaluate_promise)
  3: capture(act$val <- eval_bare(get_expr(quo), get_env(quo)))
  4: withr::with_output_sink(temp, withCallingHandlers(withVisible(code), warning = handle_warning, 
         message = handle_message))
  5: force(code)
  6: withCallingHandlers(withVisible(code), warning = handle_warning, message = handle_message)
  7: withVisible(code)
  8: eval_bare(get_expr(quo), get_env(quo))
  9: store_bikedata(data_dir = tempdir(), bikedb = bikedb, quiet = TRUE)
  10: stop("No stations returned; please try again")

  == testthat results  ===========================================================
  OK: 139 SKIPPED: 3 FAILED: 1
  1. Error: write and store data (@test-store-data.R#44) 

These tests have to be skipped on CRAN