Sort the results before comparison

The SQL statements don't contain an `ORDER BY` clause, so the ordering
can't be an intentional check for this exercise. This exercise happens
to work most of the time because BigQuery tends to return results in the
same order, but sometimes it doesn't. Learn users shouldn't have to deal
with this non-determinism in the check.

http://b/415948668

Author: jplotts

learntools/sql/ex6.py

@@ -186,14 +186,17 @@ def check(self, query, results):
         assert ('group by' in lower_query), ('Your query should have a **GROUP BY** clause.')
         assert ('count' in lower_query), ('Your query should have a **COUNT** in the **SELECT** statement.')
         assert ('%bigquery' in lower_query), ('Your **WHERE** clause is not filtering on the "bigquery" tag correctly.')
+
         # check 2: column names
         results.columns = [c.lower() for c in results.columns]
         assert ('user_id' in results.columns), ('You do not have a `user_id` column in your results.')
         assert ('number_of_answers' in results.columns), ('You do not have a `number_of_answers` column in your results.')
+
         # check 3: correct user IDs
         correct_ids = bigquery_experts_answer.loc[bigquery_experts_answer.user_id.notna(), "user_id"].unique()
         submitted_ids = results.loc[results.user_id.notna(), "user_id"].unique()
-        assert np.array_equal(correct_ids, submitted_ids), 'You seem to have the wrong values in the `user_id` column.'
+        assert np.array_equal(np.sort(correct_ids), np.sort(submitted_ids)), 'You seem to have the wrong values in the `user_id` column.'
+
         # check 4: check one value from other column
         first_id = list(bigquery_experts_answer["user_id"])[0]
         correct_num = int(bigquery_experts_answer[bigquery_experts_answer["user_id"] == first_id]["number_of_answers"])