Martin von Zweigbergk <martinvonz@google.com> [Thu, 22 Oct 2020 13:56:01 -0700] rev 45841
errors: set detailed exit code to 30 for config errors
This is per https://www.mercurial-scm.org/wiki/ErrorCategoriesPlan.
Differential Revision: https://phab.mercurial-scm.org/D9311