Fix flaky spec helper

Locally, it was not running flaky specs, because I forgot
to add the normal run when we are not in the CI.

I noticed this by running specs locally and seeing that
flaky were skipped.

core/lib/spree/testing_support/flaky.rb

@@ -15,6 +15,8 @@
   config.around(:each, :flaky) do |example|
     if ENV['CI']
       example.run_with_retry retry: 2
+    else
+      example.run
     end
   end
 end