### 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)

glDeleteFramebuffers(1, &state.shadow_fb);
			glDeleteTextures(1, &state.shadow_texture);
			glDeleteRenderbuffers(1, &state.shadow_depth_buffer);
			state.shadow_fb = 0;
			state.shadow_texture = 0;
			state.shadow_depth_buffer = 0;
			WARN_PRINT("Could not create CanvasItem shadow atlas, status: " + GLES3::TextureStorage::get_singleton()->get_framebuffer_error(status));
		}
		glBindFramebuffer(GL_FRAMEBUFFER, GLES3::TextureStorage::system_fbo);
	}
}
void RasterizerCanvasGLES3::render_sdf(RID p_render_target, LightOccluderInstance *p_occluders) {
	GLES3::TextureStorage *texture_storage = GLES3::TextureStorage::get_singleton();
	GLuint fb = texture_storage->render_target_get_sdf_framebuffer(p_render_target);
	Rect2i rect = texture_storage->render_target_get_sdf_rect(p_render_target);
	Transform2D to_sdf;
	to_sdf.columns[0] *= rect.size.width;
	to_sdf.columns[1] *= rect.size.height;
	to_sdf.columns[2] = rect.position;
	Transform2D to_clip;
	to_clip.columns[0] *= 2.0;
	to_clip.columns[1] *= 2.0;
	to_clip.columns[2] = -Vector2(1.0, 1.0);
	to_clip = to_clip * to_sdf.affine_inverse();
	glBindFramebuffer(GL_FRAMEBUFFER, fb);
	glViewport(0, 0, rect.size.width, rect.size.height);
	glDepthMask(GL_FALSE);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_BLEND);
	glDisable(GL_CULL_FACE);