re2: byteify some regex used to get check re2 availability
Changeset 687b865b95ad failed to properly byteify this because it was a raw
string. This went undetected so far because re2 does not seems to be widely
tested.
Differential Revision: https://phab.mercurial-scm.org/D10064
edition = "2018"
max_width = 79
wrap_comments = true
error_on_line_overflow = true