### Godot version

4.0 beta 10

### System information

Windows 10, Vulkan Renderer

### Issue description

In 2D scenes with sprites, when the sprite's `flip_h` and/or `flip_v` property is enabled, the normal map is flipped with the image, causing lighting to be reversed. While this does technically make sense, in a game where You have a bunch of sprites that flip and use normal maps, the only solution is to generate normal maps for both facing directions.
![image](https://user-images.githubusercontent.com/47702559/209426338-6257d66c-a965-4793-a7bb-5a635a136267.png)

Ultimately the fix is simple: Invert the red channel in normal maps on horizontally flipped sprites, and invert the green channel on vertically flipped sprites.

### Steps to reproduce

1) Create a Sprite2D
2) Add a Diffuse Texture and Normal Map 
3) Add a 2D Light to the scene
4) Enable `flip_h` and/or `flip_v` on the Sprite2D

### Minimal reproduction project

[Normal not flipped.zip](https://github.com/godotengine/godot/files/10298203/Normal.not.flipped.zip)

lights[light_count >> 2] |= light_index << ((light_count & 3) * 8);
				light_count++;
				if (light_count == data.max_lights_per_item) {
					break;
				}
			}
			light = light->next_ptr;
		}
		base_flags |= light_count << FLAGS_LIGHT_COUNT_SHIFT;
	}
	bool lights_disabled = light_count == 0 && !state.using_directional_lights;
	if (lights_disabled != state.canvas_instance_batches[state.current_batch_index].lights_disabled) {
		_new_batch(r_batch_broken, r_index);
		state.canvas_instance_batches[state.current_batch_index].lights_disabled = lights_disabled;
	}
	const Item::Command *c = p_item->commands;
	while (c) {
		if (skipping && c->type != Item::Command::TYPE_ANIMATION_SLICE) {
			c = c->next;
			continue;
		}
		if (c->type != Item::Command::TYPE_MESH) {
			
			_update_transform_2d_to_mat2x3(base_transform * draw_transform, state.instance_data_array[r_index].world);
		}
		
		for (int i = 0; i < 4; i++) {
			state.instance_data_array[r_index].modulation[i] = 0.0;
			state.instance_data_array[r_index].ninepatch_margins[i] = 0.0;
			state.instance_data_array[r_index].src_rect[i] = 0.0;