Fix python3 compatibility.

dulwich/protocol.py

@@ -109,7 +109,7 @@ def extract_capability_names(capabilities):
 
 
 def parse_capability(capability):
-    parts = capability.split('=', 1)
+    parts = capability.split(b'=', 1)
     if len(parts) == 1:
         return (parts[0], None)
     return tuple(parts)

dulwich/tests/test_server.py

@@ -133,7 +133,7 @@ class HandlerTestCase(TestCase):
     def test_capability_line(self):
         self.assertEqual(
                 b' cap1 cap2 cap3',
-                self._handler.capability_line(['cap1', 'cap2', 'cap3']))
+                self._handler.capability_line([b'cap1', b'cap2', b'cap3']))
 
     def test_set_client_capabilities(self):
         set_caps = self._handler.set_client_capabilities