Fix that slow mouse wheel scroll has no zoom effect on 2D editor

* scroll_vec in ViewPanner::gui_input is multiplied by float factors, 
  so it should be a Vector2 rather than Vector2i
* Fixes #57423

scene/gui/view_panner.cpp

@@ -37,7 +37,7 @@
 bool ViewPanner::gui_input(const Ref<InputEvent> &p_event, Rect2 p_canvas_rect) {
 	Ref<InputEventMouseButton> mb = p_event;
 	if (mb.is_valid()) {
-		Vector2i scroll_vec = Vector2((mb->get_button_index() == MouseButton::WHEEL_RIGHT) - (mb->get_button_index() == MouseButton::WHEEL_LEFT), (mb->get_button_index() == MouseButton::WHEEL_DOWN) - (mb->get_button_index() == MouseButton::WHEEL_UP));
+		Vector2 scroll_vec = Vector2((mb->get_button_index() == MouseButton::WHEEL_RIGHT) - (mb->get_button_index() == MouseButton::WHEEL_LEFT), (mb->get_button_index() == MouseButton::WHEEL_DOWN) - (mb->get_button_index() == MouseButton::WHEEL_UP));
 		if (scroll_vec != Vector2()) {
 			if (control_scheme == SCROLL_PANS) {
 				if (mb->is_ctrl_pressed()) {