chore: Mark Facebook accounts for reconnection (#2405)

fixes: #2037

spec/models/channel/facebook_page_spec.rb

@@ -13,6 +13,17 @@ RSpec.describe Channel::FacebookPage do
 
   describe 'concerns' do
     it_behaves_like 'reauthorizable'
+
+    context 'when prompt_reauthorization!' do
+      it 'calls channel notifier mail for facebook' do
+        admin_mailer = double
+        mailer_double = double
+        expect(AdministratorNotifications::ChannelNotificationsMailer).to receive(:with).and_return(admin_mailer)
+        expect(admin_mailer).to receive(:facebook_disconnect).with(channel.inbox).and_return(mailer_double)
+        expect(mailer_double).to receive(:deliver_later)
+        channel.prompt_reauthorization!
+      end
+    end
   end
 
   it 'has a valid name' do