obsolete: don't import from .node twice

See d55b71393907.

Differential Revision: https://phab.mercurial-scm.org/D12121

mercurial/obsolete.py

@@ -73,10 +73,6 b' import errno'
 import struct
 
 from .i18n import _
-from .node import (
-    bin,
-    hex,
-)
 from .pycompat import getattr
 from .node import (
     bin,