Use migrate_data option for globalize

This way the task to migrate the data doesn't have to be run manually if
these migrations weren't already executed.

db/migrate/20180730120800_add_homepage_content_translations.rb

@@ -2,10 +2,13 @@ class AddHomepageContentTranslations < ActiveRecord::Migration
 
   def self.up
     Widget::Card.create_translation_table!(
-      label:       :string,
-      title:       :string,
-      description: :text,
-      link_text:   :string
+      {
+        label:       :string,
+        title:       :string,
+        description: :text,
+        link_text:   :string
+      },
+      { migrate_data: true }
     )
   end