Morph target can not extract normal

[xiazhibin]

Godot version

0.13.1

System information

linux

Issue description

I have a simple fbx with morph targets which blender converteed to glb with morph normal but Fbx2GLTF not

There is the model: https://drive.google.com/file/d/13YsMlEXNDdoW_8hu53CT7ScSLnzc589o/view?usp=sharing

Steps to reproduce

null

Minimal reproduction project

null

[fire]

cube_morph2.fbx.zip

Minimal reproduction project.