### 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)

{
		RD::Uniform u;
		u.uniform_type = RD::UNIFORM_TYPE_TEXTURE;
		u.binding = 6;
		RID screen;
		if (p_backbuffer) {
			screen = texture_storage->render_target_get_rd_texture(p_to_render_target);
		} else {
			screen = texture_storage->render_target_get_rd_backbuffer(p_to_render_target);
			if (screen.is_null()) { 
				screen = RendererRD::TextureStorage::get_singleton()->texture_rd_get_default(RendererRD::TextureStorage::DEFAULT_RD_TEXTURE_WHITE);
			}
		}
		u.append_id(screen);
		uniforms.push_back(u);
	}
	{
		RD::Uniform u;
		u.uniform_type = RD::UNIFORM_TYPE_TEXTURE;
		u.binding = 7;
		RID sdf = texture_storage->render_target_get_sdf_texture(p_to_render_target);
		u.append_id(sdf);
		uniforms.push_back(u);
	}
	{
		
		Vector<RID> ids;
		ids.resize(12);
		RID *ids_ptr = ids.ptrw();
		ids_ptr[0] = material_storage->sampler_rd_get_default(RS::CANVAS_ITEM_TEXTURE_FILTER_NEAREST, RS::CANVAS_ITEM_TEXTURE_REPEAT_DISABLED);