Add link to SDG help page to Other information of interest section at main help

app/views/pages/help/_other.html.erb

@@ -3,6 +3,10 @@
 <ul class="features">
   <li><%= link_to t("pages.help.other.how_to_use", org_name: setting["org_name"]), how_to_use_path %></li>
 
+  <% if feature?(:sdg) %>
+    <li><%= link_to t("pages.help.other.sdg"), sdg_help_path %></li>
+  <% end %>
+
   <% SiteCustomization::Page.with_more_info_flag.with_same_locale.each do |custom_page| %>
     <li><%= link_to custom_page.title, page_path(custom_page.slug) %></li>
   <% end %>

config/locales/en/pages.yml

@@ -56,6 +56,7 @@ en:
       other:
         title: "Other information of interest"
         how_to_use: "Use %{org_name} in your city"
+        sdg: "Sustainable Development Goals help"
       how_to_use:
         text: |-
           Use it in your local government or help us to improve it, it is free software.

config/locales/es/pages.yml

@@ -56,6 +56,7 @@ es:
       other:
         title: "Otra información de interés"
         how_to_use: "Utiliza %{org_name} en tu municipio"
+        sdg: "Ayuda Objetivos de Desarrollo Sostenible"
       how_to_use:
         text: |-
           Utilízalo en tu municipio libremente o ayúdanos a mejorarlo, es software libre.

spec/system/help_page_spec.rb

@@ -25,4 +25,27 @@ describe "Help page" do
       expect(page).not_to have_link "Help"
     end
   end
+
+  scenario "renders the SDG help page link when the feature is enabled" do
+    Setting["feature.help_page"] = true
+    Setting["feature.sdg"] = true
+
+    visit root_path
+    within("#navigation_bar") do
+      click_link "Help"
+    end
+
+    expect(page).to have_link "Sustainable Development Goals help", href: sdg_help_path
+  end
+
+  scenario "does not render the SDG help page link when the feature is disabled" do
+    Setting["feature.sdg"] = nil
+
+    visit root_path
+    within("#navigation_bar") do
+      click_link "Help"
+    end
+
+    expect(page).not_to have_link "Sustainable Development Goals help"
+  end
 end