Remove models that have not been updated

[cx20]

I compared the models of Khronos' glTF-Sample-Models repository with the gltf-test repository, I noticed that there were some models that were not updated.
Therefore, I would like to remove models that have not been updated.

Khronos's glTF-Sample-Models:
https://github.com/KhronosGroup/glTF-Sample-Models/tree/master/2.0

gltf-test:
https://github.com/cx20/gltf-test/tree/master/sampleModels
https://github.com/cx20/gltf-test/tree/master/tutorialModels

gltfTutorialModels:
https://github.com/javagl/gltfTutorialModels/tree/2.0

glTF-Sample-Models	gltf-test (Current)	gltf-test (Next)
2.0/2CylinderEngine	sampleModels/2CylinderEngine
	tutorialModels/AdvancedMaterial	❌
2.0/AnimatedCube	tutorialModels/AnimatedCube
2.0/AnimatedMorphCube	tutorialModels/AnimatedMorphCube
2.0/AnimatedMorphSphere	tutorialModels/AnimatedMorphSphere
2.0/AnimatedTriangle	tutorialModels/AnimatedTriangle
2.0/Avocado	tutorialModels/Avocado
2.0/BarramundiFish	tutorialModels/BarramundiFish
2.0/BoomBox	tutorialModels/BoomBox
2.0/Box	sampleModels/Box
2.0/BoxAnimated	sampleModels/BoxAnimated
2.0/BoxInterleaved	sampleModels/BoxInterleaved
	sampleModels/BoxSemantics	❌
2.0/BoxTextured	sampleModels/BoxTextured
	sampleModels/BoxWithoutIndices	❌
2.0/BrainStem	sampleModels/BrainStem
2.0/Buggy	sampleModels/Buggy
2.0/Cameras	tutorialModels/Cameras
2.0/CesiumMan	sampleModels/CesiumMan
2.0/CesiumMilkTruck	sampleModels/CesiumMilkTruck
2.0/Corset	tutorialModels/Corset
2.0/Cube	tutorialModels/Cube
2.0/DamagedHelmet	tutorialModels/DamagedHelmet
2.0/Duck	sampleModels/Duck
2.0/GearboxAssy	sampleModels/GearboxAssy
2.0/Lantern	tutorialModels/Lantern
2.0/MetalRoughSpheres	tutorialModels/MetalRoughSpheres
2.0/Monster	sampleModels/Monster
2.0/NormalTangentTest	tutorialModels/NormalTangentTest
2.0/ReciprocatingSaw	sampleModels/ReciprocatingSaw
2.0/RiggedFigure	sampleModels/RiggedFigure
2.0/RiggedSimple	sampleModels/RiggedSimple
2.0/SciFiHelmet	tutorialModels/SciFiHelmet
	sampleModels/SmilingFace	❌
	tutorialModels/SimpleMaterial	✅ (copy from gltfTutorialModels)
2.0/SimpleMeshes	tutorialModels/SimpleMeshes
	tutorialModels/SimpleMorph
	tutorialModels/SimpleOpacity	❌
	tutorialModels/SimpleSkin	✅ (copy from gltfTutorialModels)
	tutorialModels/SimpleSparseAccessor
	tutorialModels/SimpleTexture	✅ (copy from gltfTutorialModels)
2.0/Suzanne	tutorialModels/Suzanne
2.0/TextureCoordinateTest	tutorialModels/TextureCoordinateTest
2.0/TextureSettingsTest	tutorialModels/TextureSettingsTest
2.0/Triangle	tutorialModels/Triangle
2.0/TriangleWithoutIndices	tutorialModels/TriangleWithoutIndices
2.0/TwoSidedPlane	tutorialModels/TwoSidedPlane
2.0/VC	sampleModels/VC
2.0/WaterBottle	tutorialModels/WaterBottle
	sampleModels/WalkingLady	❌