### 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)

return false;
}
bool RendererCanvasRenderRD::CanvasShaderData::casts_shadows() const {
	return false;
}
RS::ShaderNativeSourceCode RendererCanvasRenderRD::CanvasShaderData::get_native_source_code() const {
	RendererCanvasRenderRD *canvas_singleton = static_cast<RendererCanvasRenderRD *>(RendererCanvasRender::singleton);
	return canvas_singleton->shader.canvas_shader.version_get_native_source_code(version);
}
RendererCanvasRenderRD::CanvasShaderData::~CanvasShaderData() {
	RendererCanvasRenderRD *canvas_singleton = static_cast<RendererCanvasRenderRD *>(RendererCanvasRender::singleton);
	ERR_FAIL_COND(!canvas_singleton);
	
	if (version.is_valid()) {
		canvas_singleton->shader.canvas_shader.version_free(version);
	}
}
RendererRD::MaterialStorage::ShaderData *RendererCanvasRenderRD::_create_shader_func() {
	CanvasShaderData *shader_data = memnew(CanvasShaderData);
	return shader_data;
}
bool RendererCanvasRenderRD::CanvasMaterialData::update_parameters(const HashMap<StringName, Variant> &p_parameters, bool p_uniform_dirty, bool p_textures_dirty) {
	RendererCanvasRenderRD *canvas_singleton = static_cast<RendererCanvasRenderRD *>(RendererCanvasRender::singleton);
	return update_parameters_uniform_set(p_parameters, p_uniform_dirty, p_textures_dirty, shader_data->uniforms, shader_data->ubo_offsets.ptr(), shader_data->texture_uniforms, shader_data->default_texture_params, shader_data->ubo_size, uniform_set, canvas_singleton->shader.canvas_shader.version_get_shader(shader_data->version, 0), MATERIAL_UNIFORM_SET, false);
}
RendererCanvasRenderRD::CanvasMaterialData::~CanvasMaterialData() {