Don't use deprecated assertEquals.

dulwich/tests/test_porcelain.py

@@ -530,10 +530,10 @@ class StatusTests(PorcelainTestCase):
 
     def test_empty(self):
         results = porcelain.status(self.repo)
-        self.assertEquals(
+        self.assertEqual(
             {'add': [], 'delete': [], 'modify': []},
             results.staged)
-        self.assertEquals([], results.unstaged)
+        self.assertEqual([], results.unstaged)
 
     def test_status(self):
         """Integration test for `status` functionality."""