### Godot version

4.1.1 stable

### System information

Windows 10

### Issue description

this is the default size loaded on startup 1024 which seems fine but it actually have loaded the default [2048] and ignored the size in project settings
![image](https://github.com/godotengine/godot/assets/53877170/c8c71de7-468a-487f-8e6c-dba1ce0f8fa5)

changing it now to any size will break it 
[2048]
![image](https://github.com/godotengine/godot/assets/53877170/3082ff09-b7d7-41f7-8fbb-813074a54135)

[512]
![image](https://github.com/godotengine/godot/assets/53877170/5ea4620f-52b5-4d0e-a5f5-747e777cd59d)


### Steps to reproduce

change 2d shadow atlas size in project settings while using compatibility renderer. 

### Minimal reproduction project

_
state.instance_data_array[r_index].flags |= FLAGS_FLIP_V;
					}
					if (rect->flags & CANVAS_RECT_TRANSPOSE) {
						state.instance_data_array[r_index].flags |= FLAGS_TRANSPOSE_RECT;
					}
					if (rect->flags & CANVAS_RECT_CLIP_UV) {
						state.instance_data_array[r_index].flags |= FLAGS_CLIP_RECT_UV;
					}
				} else {
					dst_rect = Rect2(rect->rect.position, rect->rect.size);
					if (dst_rect.size.width < 0) {
						dst_rect.position.x += dst_rect.size.width;
						dst_rect.size.width *= -1;
					}
					if (dst_rect.size.height < 0) {
						dst_rect.position.y += dst_rect.size.height;
						dst_rect.size.height *= -1;
					}
					src_rect = Rect2(0, 0, 1, 1);
				}
				if (rect->flags & CANVAS_RECT_MSDF) {
					state.instance_data_array[r_index].flags |= FLAGS_USE_MSDF;
					state.instance_data_array[r_index].msdf[0] = rect->px_range; 
					state.instance_data_array[r_index].msdf[1] = rect->outline; 
					state.instance_data_array[r_index].msdf[2] = 0.f; 
					state.instance_data_array[r_index].msdf[3] = 0.f; 
				} else if (rect->flags & CANVAS_RECT_LCD) {
					state.instance_data_array[r_index].flags |= FLAGS_USE_LCD;
				}
				state.instance_data_array[r_index].modulation[0] = rect->modulate.r * base_color.r;