tests/helper-killhook.py

tests: also test spaces in conflict marker labels

Our fake merge tool printed the arguments using `$1` etc. without
quotes, which means that the shell collapsed repeated spaces within
the argument. That resulted in tests that did not pick up changes to
the number of spaces.

Differential Revision: https://phab.mercurial-scm.org/D12010

import os


def killme(ui, repo, hooktype, **wkargs):
    os._exit(80)