### 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)

glDisable(GL_SCISSOR_TEST);
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);
	CanvasOcclusionShaderGLES3::ShaderVariant variant = CanvasOcclusionShaderGLES3::MODE_SDF;
	bool success = shadow_render.shader.version_bind_shader(shadow_render.shader_version, variant);
	if (!success) {
		return;
	}
	shadow_render.shader.version_set_uniform(CanvasOcclusionShaderGLES3::PROJECTION, Projection(), shadow_render.shader_version, variant);
	shadow_render.shader.version_set_uniform(CanvasOcclusionShaderGLES3::DIRECTION, 0.0, 0.0, shadow_render.shader_version, variant);
	shadow_render.shader.version_set_uniform(CanvasOcclusionShaderGLES3::Z_FAR, 0.0, shadow_render.shader_version, variant);
	LightOccluderInstance *instance = p_occluders;
	while (instance) {
		OccluderPolygon *oc = occluder_polygon_owner.get_or_null(instance->occluder);
		if (!oc || oc->sdf_vertex_array == 0) {
			instance = instance->next;
			continue;
		}
		Transform2D modelview = to_clip * instance->xform_cache;
		shadow_render.shader.version_set_uniform(CanvasOcclusionShaderGLES3::MODELVIEW1, modelview.columns[0][0], modelview.columns[1][0], 0, modelview.columns[2][0], shadow_render.shader_version, variant);
		shadow_render.shader.version_set_uniform(CanvasOcclusionShaderGLES3::MODELVIEW2, modelview.columns[0][1], modelview.columns[1][1], 0, modelview.columns[2][1], shadow_render.shader_version, variant);
		glBindVertexArray(oc->sdf_vertex_array);
		glDrawElements(oc->sdf_is_lines ? GL_LINES : GL_TRIANGLES, oc->sdf_index_count, GL_UNSIGNED_INT, 0);
		instance = instance->next;
	}
	texture_storage->render_target_sdf_process(p_render_target); 
	glBindVertexArray(0);
	glBindFramebuffer(GL_FRAMEBUFFER, 0);
}
RID RasterizerCanvasGLES3::occluder_polygon_create() {