feat: Add Instagram Channel (#2955)

db/migrate/20210902181438_add_instagram_id_to_facebook_page.rb

@@ -0,0 +1,9 @@
+class AddInstagramIdToFacebookPage < ActiveRecord::Migration[6.1]
+  def up
+    add_column :channel_facebook_pages, :instagram_id, :string
+  end
+
+  def down
+    remove_column :channel_facebook_pages, :instagram_id, :string
+  end
+end