py3: byte-prefix sanitisation regexes in phabricator.py
So it doesn't die with "TypeError: cannot use a string pattern on a bytes-like
object".
Differential Revision: https://phab.mercurial-scm.org/D6863
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ echo 'base' > base
$ hg ci -Ambase
adding base
$ hg qnew -mmqbase mqbase
$ hg qsave
$ hg qrestore 2
restoring status: hg patches saved state