Add Capybara::DSL to visual_regression tests

It doesn't strike me that they'll ever be a scenario where we want
visual regression tests without capybara. Therefore I've added the
visual_regression tag as one to also use the Capybara::DSL.

While doing this I took the liberty to update the visual_regression tag
usage to be the short form.

spec/rails_helper.rb

@@ -10,7 +10,7 @@
 Selenium::WebDriver::Options.chrome(loggingPrefs: { browser: "ALL" })
 
 RSpec.configure do |config|
-  config.include Capybara::DSL, capybara: true
+  config.include Capybara::DSL, capybara: true, visual_regression: true
   config.include Helpers::Components, type: :view
   config.include ActiveSupport::Testing::TimeHelpers
 end

spec/visual_regression_tests/all_components_spec.rb

@@ -2,7 +2,7 @@
 require "percy/capybara"
 require "uri"
 
-describe "visual regression test runner Percy", visual_regression: true do
+describe "visual regression test runner Percy", :visual_regression do
   it "takes a screenshot of each component" do
     # Freeze time for consistency
     travel_to Time.zone.local(2020, 12, 1, 6, 0, 0)