Fix URL hint triggering

BUG: 428279

For some reason we don't get the key event with ctrl+alt+0, I'll look into that as well.

edit: checked with a simple qt-only testcase, and qt delivers key events (QKeyEvent(KeyPress, Key_0, ControlModifier|AltModifier, text="0")), but it never arrives in TerminalDisplay::keyPressEvent. So something in Konsole is eating it (might be kxmlgui or something).

edit2: even weirder, TerminalDisplay::keyReleaseEvent receives it (QKeyEvent(KeyRelease, Key_0, ControlModifier|AltModifier, text="0"))...

edit3: it's the shortcut for "reset font size" that eats it: collection->setDefaultShortcut(action, Konsole::ACCEL + Qt::ALT + Qt::Key_0);