throttle preprints for production tests

Author: jh27539

tests/test_preprints.py

@@ -1313,6 +1313,7 @@ def test_submit_page_loads(self, driver, provider):
 
 
 @markers.smoke_test
+@pytest.mark.usefixtures('throttle_on_prod')
 @pytest.mark.skipif(
     not settings.PRODUCTION,
     reason='Most of the Branded Preprint Provider pages in test environments have no preprints',