fix: use templater to substitute values in command string
bytes.format() isn't supported on Python 3. Luckily, our template syntax
is similar so we can reuse it. We need a hack to disable \-escapes as '\'
is a directory separator on Windows.
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}