py3: fix test-update-atomic.t...
py3: fix test-update-atomic.t
The .replace('o', '') hack on oct() return value is required because:
% python -c 'print(oct(10))'
012
% python3 -c 'print(oct(10))'
0o12
Differential Revision:
https://phab.mercurial-scm.org/D5684