As of v0.18.1 I can use `test_bitcoin-qt -platform cocoa` to run GUI tests; this opens and closes a regtest GUI a bunch of times.

As of master (6e4f6553913978fcdddba30e0bb6f97edcb12e80) it seems to ignore the `-platform cocoa` and just run the test as with `minimal`.

As seen on macOS 10.14.6. Git bisect blames a2714a5c69f0b0506689af04c3e785f71ee0915d in #16578 `Do not pass in command line arguments to QApplication` (@achow101, @ryanofsky)
{
    QTableView* table = view.findChild<QTableView*>("transactionView");
    QModelIndex index = FindTx(*table->selectionModel()->model(), txid);
    QVERIFY2(index.isValid(), "Could not find BumpFee txid");
    
    
    QAction* action = view.findChild<QAction*>("bumpFeeAction");
    table->selectionModel()->select(index, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows);
    action->setEnabled(expectDisabled);
    table->customContextMenuRequested({});
    QCOMPARE(action->isEnabled(), !expectDisabled);
    action->setEnabled(true);
    QString text;
    if (expectError.empty()) {
        ConfirmSend(&text, cancel);
    } else {
        ConfirmMessage(&text);
    }
    action->trigger();
    QVERIFY(text.indexOf(QString::fromStdString(expectError)) != -1);
}
void TestGUI()