wireprotov1server: capture Abort type before accessing the `hint` attribute Although the previous code worked, pytypes complained because `exc` is caught above as `BundleValueError, Abort, PushRaced`, and the other two don't have this attribute. Differential Revision: https://phab.mercurial-scm.org/D7463

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