Fix typo in test_array.py (GH-23189)

diff --git a/Lib/test/test_array.py b/Lib/test/test_array.py
index c423f54..77a0c64 100644
--- a/Lib/test/test_array.py
+++ b/Lib/test/test_array.py
@@ -393,7 +393,7 @@ def test_exhausted_reverse_iterator(self):
         a.insert(0, self.outside)
         self.assertEqual(list(exhit), [])
         # The iterator index points past the 0th position so inserting
-        # an element in the beggining does not make it appear.
+        # an element in the beginning does not make it appear.
         self.assertEqual(list(empit), [])
         self.assertEqual(list(a), [self.outside] + list(self.example))