Fixed flaky test

functional_tests/test_export_modal.py

@@ -112,6 +112,7 @@ class ExportTestModal(LiveServerTestCase):
 
     def test_export_student_scores_as_json(self):
         fact.StudentInfoFactory()
+        fact.SubmissionFactory()
         self._login()
         export_btn = self.browser.find_element_by_id('export-btn')
         export_btn.click()