Use cuprite to drive Chrome (#60)

headless tests started to fail due to elements not being present in time
or not being found period.  CBA to fix so just switch to this other
driver for now.

Reviewed-on: #60

test/application_system_test_case.rb

@@ -1,9 +1,8 @@
 require "test_helper"
+require "capybara/cuprite"
 
 class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
-  driven_by :selenium,
-    using: ENV["VISIBLE_SYSTEM_TESTS"].present? ? :chrome : :headless_chrome,
-    screen_size: [ 1400, 1400 ]
+  driven_by :cuprite, options: { headless: ENV["VISIBLE_SYSTEM_TESTS"].blank? }
 
   def login(email, password = "secret")
     visit new_session_url