### 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
scroll->set_focus_mode(FOCUS_CLICK);
	scroll->connect("gui_input", callable_mp(this, &AnimationTrackEditor::_scroll_input));
	scroll->connect("focus_exited", callable_mp(panner.ptr(), &ViewPanner::release_pan_key));
	bezier_edit = memnew(AnimationBezierTrackEdit);
	timeline_vbox->add_child(bezier_edit);
	bezier_edit->set_editor(this);
	bezier_edit->set_timeline(timeline);
	bezier_edit->hide();
	bezier_edit->set_v_size_flags(SIZE_EXPAND_FILL);
	bezier_edit->connect("close_request", callable_mp(this, &AnimationTrackEditor::_cancel_bezier_edit));
	timeline_vbox->set_custom_minimum_size(Size2(0, 150) * EDSCALE);
	hscroll = memnew(HScrollBar);
	hscroll->share(timeline);
	hscroll->hide();
	hscroll->connect("value_changed", callable_mp(this, &AnimationTrackEditor::_update_scroll));
	timeline_vbox->add_child(hscroll);
	timeline->set_hscroll(hscroll);
	track_vbox = memnew(VBoxContainer);
	scroll->add_child(track_vbox);
	track_vbox->set_h_size_flags(SIZE_EXPAND_FILL);
	scroll->set_horizontal_scroll_mode(ScrollContainer::SCROLL_MODE_DISABLED);
	track_vbox->add_theme_constant_override("separation", 0);
	HBoxContainer *bottom_hb = memnew(HBoxContainer);
	add_child(bottom_hb);
	imported_anim_warning = memnew(Button);
	imported_anim_warning->hide();
	imported_anim_warning->set_text(TTR("Imported Scene"));
	imported_anim_warning->set_tooltip_text(TTR("Warning: Editing imported animation"));
	imported_anim_warning->connect("pressed", callable_mp(this, &AnimationTrackEditor::_show_imported_anim_warning));
	bottom_hb->add_child(imported_anim_warning);