Compatibility with Mercurial 6.4
The only change we had to make is a workaround for what appears to be a minor bug in Mercurial or, if it is intended that some cache has to be updated explicitely, a missing compatibility in `mercurial-testhelper`.
This instance will be upgraded to Heptapod 17.9.2 on 2025-04-24 between 17:00 and 18:00 UTC+2
The only change we had to make is a workaround for what appears to be a minor bug in Mercurial or, if it is intended that some cache has to be updated explicitely, a missing compatibility in `mercurial-testhelper`.
mentioned in commit 7673af19ea23