tests: set old git default branch name for compatibility...
tests: set old git default branch name for compatibility
Git's default branch name has changed on my machine (from "master" to
"main"). Let's set the old name in our tests so we're compatible with
both defaults (and maybe still compatible with Git versions that don't
know about the config option).
Differential Revision:
https://phab.mercurial-scm.org/D9470
