### 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
Variant old = args[idx];
							Variant *ptrs[1] = { &old };
							Variant::construct(t, args.write[idx], (const Variant **)ptrs, 1, err);
						} else {
							Variant::construct(t, args.write[idx], nullptr, 0, err);
						}
						change_notify_deserved = true;
						d_new["args"] = args;
					}
				} else if (what == "value") {
					Variant value = p_value;
					if (value.get_type() == Variant::NODE_PATH) {
						_fix_node_path(value);
					}
					args.write[idx] = value;
					d_new["args"] = args;
					mergeable = true;
				}
			}
			if (mergeable) {
				undo_redo->create_action(TTR("Animation Change Call"), UndoRedo::MERGE_ENDS);
			} else {
				undo_redo->create_action(TTR("Animation Change Call"));
			}
			setting = true;
			undo_redo->add_do_method(animation.ptr(), "track_set_key_value", track, key, d_new);
			undo_redo->add_undo_method(animation.ptr(), "track_set_key_value", track, key, d_old);
			undo_redo->add_do_method(this, "_update_obj", animation);
			undo_redo->add_undo_method(this, "_update_obj", animation);
			undo_redo->commit_action();