fix flaky test

Author: marcoacierno

backend/api/submissions/tests/test_submissions.py

@@ -87,14 +87,22 @@ def test_returns_submissions_paginated(graphql_client, user):
     )
 
     assert not resp.get("errors")
-    assert resp["data"]["submissions"]["items"] == [{"id": submission_2.hashid}]
+    assert len(resp["data"]["submissions"]["items"]) == 1
+    item = resp["data"]["submissions"]["items"][0]
     assert resp["data"]["submissions"]["pageInfo"] == {"totalPages": 2, "totalItems": 2}
 
     resp_2 = graphql_client.query(
         query,
         variables={"code": submission.conference.code, "page": 2},
     )
-    assert resp_2["data"]["submissions"]["items"] == [{"id": submission.hashid}]
+
+    assert not resp_2.get("errors")
+    assert len(resp_2["data"]["submissions"]["items"]) == 1
+    item_2 = resp_2["data"]["submissions"]["items"][0]
+
+    assert set([item["id"], item_2["id"]]) == set(
+        [submission.hashid, submission_2.hashid]
+    )
 
 
 def test_canceled_submissions_are_excluded(graphql_client, user, mock_has_ticket):