### Godot version

4.1

### System information

Windows

### Issue description

Being able to have multiple cursors similarly to vscode is a great feature, however it's only possible to add carets, not remove them. By left clicking you can remove all extra cursors but you cannot remove a specific one so after selecting multiple lines a single missclick, you have to reselect them all again. Looking at the original pr there was a remove_caret function added so it would make sense to be able to remove carets when clicking again, like in vscode.

![image](https://github.com/godotengine/godot/assets/19669673/3867c00e-9faa-4429-9c6d-f2d6d3883044)


### Steps to reproduce

- Alt click to add multiple carets
- Alt click on the same position again
- Nothing happens

### Minimal reproduction project

N/A
set_caret_line(pos.y, false, true, 0, 0);
			set_caret_column(pos.x, true, 0);
			dragging_selection = true;
		}
	}
	if (draw_minimap && !dragging_selection) {
		_update_minimap_hover();
	}
	if (v_scroll->get_value() != prev_v_scroll || h_scroll->get_value() != prev_h_scroll) {
		accept_event(); 
	}
	Ref<InputEventKey> k = p_gui_input;
	if (k.is_valid()) {
		if (alt_input(p_gui_input)) {
			accept_event();
			return;
		}
		if (!k->is_pressed()) {
			return;
		}
		
		if (k->get_keycode() == Key::CTRL || k->get_keycode() == Key::ALT || k->get_keycode() == Key::SHIFT || k->get_keycode() == Key::META || k->get_keycode() == Key::CAPSLOCK) {
			return;
		}
		_reset_caret_blink_timer();
		
		
		bool allow_unicode_handling = !(k->is_command_or_control_pressed() || k->is_ctrl_pressed() || k->is_alt_pressed() || k->is_meta_pressed());