Render 'how to enable' when the related feature setting is disabled

Add 'how to enable' information on SDG configuration tab when related
sdg feature setting is disabled.

app/views/admin/settings/_sdg_configuration_tab.html.erb

@@ -1,3 +1,9 @@
-<h2><%= t("admin.settings.index.sdg.title") %></h2>
+<% if feature?(:sdg) %>
+  <h2><%= t("admin.settings.index.sdg.title") %></h2>
 
-<%= render "featured_settings_table", features: @sdg_settings, tab: "#tab-sdg-configuration" %>
+  <%= render "featured_settings_table", features: @sdg_settings, tab: "#tab-sdg-configuration" %>
+<% else %>
+  <div class="callout primary">
+    <%= t("admin.settings.index.sdg.how_to_enable") %>
+  </div>
+<% end %>

config/locales/en/admin.yml

@@ -1242,6 +1242,7 @@ en:
           how_to_enable: 'To configure remote census (SOAP) you must enable "Configure connection to remote census (SOAP)" on "Features" tab.'
         sdg:
           title: SDG configuration
+          how_to_enable: 'To show the configuration options from Sustainable Development Goals you must enable "SDG" on "Features" tab.'
       remote_census_general_name: General Information
       remote_census_request_name: Request Data
       remote_census_response_name: Response Data

config/locales/es/admin.yml

@@ -1241,6 +1241,7 @@ es:
           how_to_enable: 'Para configurar la conexión con el Censo Remoto (SOAP) se debe activar "Configurar la conexión al censo remoto (SOAP)" en la pestaña "Funcionalidades".'
         sdg:
           title: Configuración ODS
+          how_to_enable: 'Para mostrar las opciones de configuración de los Objetivos de Desarrollo Sostenible se debe activar "ODS" en la pestaña "Funcionalidades".'
       remote_census_general_name: Datos Generales
       remote_census_request_name: Datos Petición
       remote_census_response_name: Datos Respuesta

spec/system/admin/settings_spec.rb

@@ -267,6 +267,7 @@ describe "Admin settings", :admin do
     end
 
     scenario "On #tab-sdg-configuration", :js do
+      Setting["feature.sdg"] = true
       Setting.create!(key: "sdg.whatever")
       login_as(create(:administrator).user)
 
@@ -313,4 +314,28 @@ describe "Admin settings", :admin do
       Setting["feature.user.skip_verification"] = nil
     end
   end
+
+  describe "SDG configuration tab", :js do
+    scenario "is enabled when the sdg feature is enabled" do
+      Setting["feature.sdg"] = true
+      login_as(create(:administrator).user)
+
+      visit admin_settings_path
+      click_link "SDG configuration"
+
+      expect(page).to have_css "h2", exact_text: "SDG configuration"
+    end
+
+    scenario "is disabled when the sdg feature is disabled" do
+      Setting["feature.sdg"] = false
+      login_as(create(:administrator).user)
+
+      visit admin_settings_path
+      click_link "SDG configuration"
+
+      expect(page).to have_content "To show the configuration options from " \
+                                   "Sustainable Development Goals you must " \
+                                   'enable "SDG" on "Features" tab.'
+    end
+  end
 end