### 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)

1.0, 0.0
			};
			glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 16, qv, GL_STATIC_DRAW);
		}
		glBindBuffer(GL_ARRAY_BUFFER, 0); 
		glGenVertexArrays(1, &data.particle_quad_array);
		glBindVertexArray(data.particle_quad_array);
		glBindBuffer(GL_ARRAY_BUFFER, data.particle_quad_vertices);
		glEnableVertexAttribArray(RS::ARRAY_VERTEX);
		glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, nullptr);
		glEnableVertexAttribArray(RS::ARRAY_TEX_UV);
		glVertexAttribPointer(RS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 4, CAST_INT_TO_UCHAR_PTR(8));
		glBindVertexArray(0);
		glBindBuffer(GL_ARRAY_BUFFER, 0); 
	}
	
	{
		
		glGenBuffers(1, &data.ninepatch_vertices);
		glBindBuffer(GL_ARRAY_BUFFER, data.ninepatch_vertices);
		glBufferData(GL_ARRAY_BUFFER, sizeof(float) * (16 + 16) * 2, nullptr, GL_DYNAMIC_DRAW);
		glBindBuffer(GL_ARRAY_BUFFER, 0);
		
		glGenBuffers(1, &data.ninepatch_elements);
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.ninepatch_elements);
#define _EIDX(y, x) (y * 4 + x)
		uint8_t elems[3 * 2 * 9] = {
			
			_EIDX(0, 0), _EIDX(0, 1), _EIDX(1, 1),
			_EIDX(1, 1), _EIDX(1, 0), _EIDX(0, 0),