Force Capybara browser's scale factor

Prevent inconsistent behaviors when running Capybara specs with a
high-res device.

spec/support/capybara.rb

@@ -50,6 +50,10 @@ Capybara.register_driver :chrome do |app|
   )
 
   options = Selenium::WebDriver::Chrome::Options.new
+
+  # Force the browser's scale factor to prevent inconsistencies on high-res devices
+  options.add_argument('--force-device-scale-factor=1')
+
   options.add_argument("window-size=#{CAPYBARA_WINDOW_SIZE.join(',')}")
 
   # Chrome won't work properly in a Docker container in sandbox mode