rust-dirstate-v2: clean up previous data file after the docket is written This was overlooked before and caused many data files to keep living forever. We could potentially consider adding a random cleanup of them in case they slipped through one day. Differential Revision: https://phab.mercurial-scm.org/D12581

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    "phabricator.uri": "https://phab.mercurial-scm.org/",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}