profiler: flush after writing the profiler output Otherwise, the profiler output might only partially appears until the next flush of the buffer. Since profiling often happens for long operation, the next flush can be a long time away.

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