tst_QUuid::uint128 fails on big-endian

134: FAIL!  : tst_QUuid::uint128() The computed value is expected to be equal to the baseline, but is not
134:    Computed (uuid) : {d128b8c5-ee95-a43c-3644-34cc9eb569fc}
134:    Baseline (uuidA): {fc69b59e-cc34-4436-a43c-ee95d128b8c5}
134:    Loc: [/home/rutledge/dev/qt6/qtbase/tests/auto/corelib/plugin/quuid/tst_quuid.cpp(303)]

void tst_QUuid::uint128()
{
#ifdef QT_SUPPORTS_INT128
    constexpr quint128 u = Q_UINT128_C(0xfc69b59e'cc344436'a43cee95'd128b8c5); // This is LE
    constexpr quint128 be = qToBigEndian(u);
    constexpr QUuid uuid = QUuid::fromUInt128(be);
    static_assert(uuid.toUInt128() == be, "Round-trip through QUuid failed");
    
    QT_TEST_EQUALITY_OPS(uuid, uuidA, true);