### Godot version

v4.0 rc6

### System information

Windows 10

### Issue description

When using a ViewportTexture from a SubViewport on a TextureRect, it throws errors after running the scene once and then switching scenes in the editor.
![Pasted image 20230227212626](https://user-images.githubusercontent.com/44676282/221680047-984fa03e-33d1-4856-9a7f-1700b28423cf.png)


### Steps to reproduce

Run the canvas-scene once.
Switch to another scene in the editor.
Switch back to the canvas-scene

### Minimal reproduction project

[ViewportTextureError.zip](https://github.com/godotengine/godot/files/10844099/ViewportTextureError.zip)

BIND_ENUM_CONSTANT(DEBUG_DRAW_SHADOW_ATLAS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_DIRECTIONAL_SHADOW_ATLAS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_SCENE_LUMINANCE);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_SSAO);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_SSIL);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_PSSM_SPLITS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_DECAL_ATLAS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_SDFGI);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_SDFGI_PROBES);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_GI_BUFFER);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_DISABLE_LOD);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_CLUSTER_OMNI_LIGHTS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_CLUSTER_SPOT_LIGHTS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_CLUSTER_DECALS);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_CLUSTER_REFLECTION_PROBES);
	BIND_ENUM_CONSTANT(DEBUG_DRAW_OCCLUDERS)
	BIND_ENUM_CONSTANT(DEBUG_DRAW_MOTION_VECTORS)
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_NEAREST);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_LINEAR);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_LINEAR_WITH_MIPMAPS);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_NEAREST_WITH_MIPMAPS);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_MAX);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_REPEAT_DISABLED);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_REPEAT_ENABLED);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_REPEAT_MIRROR);
	BIND_ENUM_CONSTANT(DEFAULT_CANVAS_ITEM_TEXTURE_REPEAT_MAX);
	BIND_ENUM_CONSTANT(SDF_OVERSIZE_100_PERCENT);
	BIND_ENUM_CONSTANT(SDF_OVERSIZE_120_PERCENT);
	BIND_ENUM_CONSTANT(SDF_OVERSIZE_150_PERCENT);
	BIND_ENUM_CONSTANT(SDF_OVERSIZE_200_PERCENT);