Fixed typos in docs and a test comment.

[YooInKeun]

The word "the" is repeated. I propose to remove one.

[hramezani]

@YooInKeun Thanks.

There is another one in tests, this one also can be removed:

diff --git a/tests/foreign_object/tests.py b/tests/foreign_object/tests.py
index b211c6e328..a33f29a38c 100644
--- a/tests/foreign_object/tests.py
+++ b/tests/foreign_object/tests.py
@@ -47,7 +47,7 @@ class MultiColumnFKTests(TestCase):
         self.assertEqual((person.id, person.name), (self.bob.id, "Bob"))
 
     def test_get_fails_on_multicolumn_mismatch(self):
-        # Membership objects returns DoesNotExist error when the there is no
+        # Membership objects returns DoesNotExist error when there is no
         # Person with the same id and country_id
         membership = Membership.objects.create(
             membership_country_id=self.usa.id, person_id=self.jane.id, group_id=self.cia.id)

[felixxm]

@YooInKeun Thanks 👍