Extract canary toggle page url to a variable

app/views/layouts/header/_current_user_dropdown.html.haml

@@ -45,7 +45,7 @@
   = render 'shared/user_dropdown_instance_review'
   - if Gitlab.com_but_not_canary?
     %li.d-md-none
-      = link_to _("Switch to GitLab Next"), "https://next.gitlab.com/"
+      = link_to _("Switch to GitLab Next"), Gitlab::Saas.canary_toggle_com_url
 
   - if current_user_menu?(:sign_out)
     %li.divider

app/views/layouts/header/_default.html.haml

@@ -15,7 +15,7 @@
               %span.logo-text.d-none.d-lg-block.gl-ml-3
                 = logo_text
           - if Gitlab.com_and_canary?
-            = link_to 'https://next.gitlab.com', class: 'canary-badge bg-transparent', data: { qa_selector: 'canary_badge_link' }, target: :_blank, rel: :_noopener do
+            = link_to Gitlab::Saas.canary_toggle_com_url, class: 'canary-badge bg-transparent', data: { qa_selector: 'canary_badge_link' }, target: :_blank, rel: 'noopener noreferrer' do
               %span.gl-badge.gl-bg-green-500.gl-text-white.gl-rounded-pill.gl-font-weight-bold.gl-py-1
                 = _('Next')
 

app/views/layouts/header/_help_dropdown.html.haml

@@ -20,4 +20,4 @@
   = render 'shared/user_dropdown_instance_review'
   - if Gitlab.com_but_not_canary?
     %li
-      = link_to _("Switch to GitLab Next"), "https://next.gitlab.com/"
+      = link_to _("Switch to GitLab Next"), Gitlab::Saas.canary_toggle_com_url

lib/gitlab/saas.rb

@@ -13,6 +13,10 @@ module Gitlab
       'https://staging.gitlab.com'
     end
 
+    def self.canary_toggle_com_url
+      'https://next.gitlab.com'
+    end
+
     def self.subdomain_regex
       %r{\Ahttps://[a-z0-9]+\.gitlab\.com\z}.freeze
     end

spec/lib/gitlab/saas_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Saas do
+  describe '.canary_toggle_com_url' do
+    subject { described_class.canary_toggle_com_url }
+
+    let(:next_url) { 'https://next.gitlab.com' }
+
+    it { is_expected.to eq(next_url) }
+  end
+end