formatter: inline a variable assigned from `templater.templater.frommapfile`
The variable doesn't get reused and it doesn't help formatting, so I
don't see any reason for it.
Differential Revision: https://phab.mercurial-scm.org/D8807
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}