rust-clippy: factor an `if` with the same duplicated clause
Unlike the next changeset, this if is not really made clearer by keeping the
cases separate.
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"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}