### Godot version

4.2 dev3

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

If you have a Method Track with multiple calls to the same method, they are joined together and makes things unreadable:
![image](https://github.com/godotengine/godot/assets/2223172/a2ab8446-28a1-440b-b0d5-5049f5d705b4)
The horizontal line shouldn't be used here. I think it might be a regression.

### Steps to reproduce

1. Add AnimationPlayer
2. Add a Method Track (with Add Track button)
3. Add some key to the track
4. Add another key with the same method

### Minimal reproduction project

N/A
if (p_state.has("fps_mode")) {
		bool fps_mode = p_state["fps_mode"];
		if (fps_mode) {
			snap_mode->select(1);
		} else {
			snap_mode->select(0);
		}
		_snap_mode_changed(snap_mode->get_selected());
	} else {
		snap_mode->select(0);
		_snap_mode_changed(snap_mode->get_selected());
	}
	if (p_state.has("zoom")) {
		zoom->set_value(p_state["zoom"]);
	} else {
		zoom->set_value(1.0);
	}
	if (p_state.has("offset")) {
		timeline->set_value(p_state["offset"]);
	} else {
		timeline->set_value(0);
	}
	if (p_state.has("v_scroll")) {
		scroll->get_v_scroll_bar()->set_value(p_state["v_scroll"]);
	} else {
		scroll->get_v_scroll_bar()->set_value(0);
	}
}
void AnimationTrackEditor::cleanup() {