py3: add b'' prefixes in tests/test-bdiff.py
This makes the test close to passing
# skip-blame because just b'' prefixes
Differential Revision: https://phab.mercurial-scm.org/D4695
#!/bin/sh
HGENCODING=UTF-8
export HGENCODING
echo ".. -*- coding: utf-8 -*-" > gendoc.txt
echo "" >> gendoc.txt
LANGUAGE=$1 python "$TESTDIR/../doc/gendoc.py" >> gendoc.txt 2> /dev/null || exit
echo "checking for parse errors"
python "$TESTDIR/../doc/docchecker" gendoc.txt
python "$TESTDIR/../doc/runrst" html gendoc.txt /dev/null