Pierre-Yves David <pierre-yves.david@octobus.net> [Sat, 17 Jun 2023 04:05:53 +0200] rev 50398
re2: fix reporting of availability in `hg debuginstall`
We add and use an official API to check is re2 is available. This prevent the
bug previously in place were debuginstall was considering confusing `None`
(i.e. non-initialized) and `False` (i.e. unavailable).