### 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
ease_selection->add_item(TTR("OutIn", "Ease Type"), Tween::EASE_OUT_IN);
	ease_selection->select(Tween::EASE_IN_OUT); 
	ease_selection->set_auto_translate(false); 
	ease_fps = memnew(SpinBox);
	ease_fps->set_min(1);
	ease_fps->set_max(999);
	ease_fps->set_step(1);
	ease_fps->set_value(30); 
	ease_grid->add_child(memnew(Label(TTR("Transition Type:"))));
	ease_grid->add_child(transition_selection);
	ease_grid->add_child(memnew(Label(TTR("Ease Type:"))));
	ease_grid->add_child(ease_selection);
	ease_grid->add_child(memnew(Label(TTR("FPS:"))));
	ease_grid->add_child(ease_fps);
	
	bake_dialog = memnew(ConfirmationDialog);
	bake_dialog->set_title(TTR("Animation Baker"));
	bake_dialog->connect("confirmed", callable_mp(this, &AnimationTrackEditor::_edit_menu_pressed).bind(EDIT_BAKE_ANIMATION_CONFIRM));
	add_child(bake_dialog);
	GridContainer *bake_grid = memnew(GridContainer);
	bake_grid->set_columns(2);
	bake_dialog->add_child(bake_grid);
	bake_trs = memnew(CheckBox);
	bake_trs->set_pressed(true);
	bake_blendshape = memnew(CheckBox);
	bake_blendshape->set_pressed(true);
	bake_value = memnew(CheckBox);
	bake_value->set_pressed(true);
	bake_fps = memnew(SpinBox);
	bake_fps->set_min(1);