### 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)

float screen_pixel_size[2];
			float time;
			uint32_t use_pixel_snap;
			float sdf_to_tex[4];
			float sdf_to_screen[2];
			float screen_to_sdf[2];
			uint32_t directional_light_count;
			float tex_to_sdf;
			uint32_t pad1;
			uint32_t pad2;
		};
		LightUniform *light_uniforms = nullptr;
		RID lights_uniform_buffer;
		RID canvas_state_buffer;
		RID shadow_sampler;
		RID shadow_texture;
		RID shadow_depth_texture;
		RID shadow_fb;
		int shadow_texture_size = 2048;
		RID default_transforms_uniform_set;
		uint32_t max_lights_per_render;
		uint32_t max_lights_per_item;
		double time;
	} state;
	struct PushConstant {
		float world[6];
		uint32_t flags;
		uint32_t specular_shininess;
		union {