### 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)

SHADER_VARIANT_ATTRIBUTES,
						SHADER_VARIANT_ATTRIBUTES_POINTS,
						SHADER_VARIANT_QUAD,
				},
				{
						
						SHADER_VARIANT_QUAD_LIGHT,
						SHADER_VARIANT_NINEPATCH_LIGHT,
						SHADER_VARIANT_PRIMITIVE_LIGHT,
						SHADER_VARIANT_PRIMITIVE_LIGHT,
						SHADER_VARIANT_PRIMITIVE_POINTS_LIGHT,
						SHADER_VARIANT_ATTRIBUTES_LIGHT,
						SHADER_VARIANT_ATTRIBUTES_LIGHT,
						SHADER_VARIANT_ATTRIBUTES_LIGHT,
						SHADER_VARIANT_ATTRIBUTES_LIGHT,
						SHADER_VARIANT_ATTRIBUTES_POINTS_LIGHT,
						SHADER_VARIANT_QUAD_LIGHT,
				},
			};
			RID shader_variant = canvas_singleton->shader.canvas_shader.version_get_shader(version, shader_variants[i][j]);
			if (j == PIPELINE_VARIANT_QUAD_LCD_BLEND) {
				pipeline_variants.variants[i][j].setup(shader_variant, primitive[j], RD::PipelineRasterizationState(), RD::PipelineMultisampleState(), RD::PipelineDepthStencilState(), blend_state_lcd, RD::DYNAMIC_STATE_BLEND_CONSTANTS);
			} else {
				pipeline_variants.variants[i][j].setup(shader_variant, primitive[j], RD::PipelineRasterizationState(), RD::PipelineMultisampleState(), RD::PipelineDepthStencilState(), blend_state, 0);
			}
		}
	}
	valid = true;
}
bool RendererCanvasRenderRD::CanvasShaderData::is_animated() const {