Remove unused material

Assets/Scenes/ImageTracking/UnlitTexture.mat

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-%TAG !u! tag:unity3d.com,2011:
---- !u!21 &2100000
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-  m_ObjectHideFlags: 0
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-  m_PrefabInstance: {fileID: 0}
-  m_PrefabAsset: {fileID: 0}
-  m_Name: UnlitTexture
-  m_Shader: {fileID: 10752, guid: 0000000000000000f000000000000000, type: 0}
-  m_ShaderKeywords: 
-  m_LightmapFlags: 4
-  m_EnableInstancingVariants: 0
-  m_DoubleSidedGI: 0
-  m_CustomRenderQueue: -1
-  stringTagMap: {}
-  disabledShaderPasses: []
-  m_SavedProperties:
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-    m_TexEnvs:
-    - _BumpMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _DetailAlbedoMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _DetailMask:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _DetailNormalMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
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-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _MainTex:
-        m_Texture: {fileID: 10305, guid: 0000000000000000f000000000000000, type: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _MetallicGlossMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _OcclusionMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    - _ParallaxMap:
-        m_Texture: {fileID: 0}
-        m_Scale: {x: 1, y: 1}
-        m_Offset: {x: 0, y: 0}
-    m_Floats:
-    - _BumpScale: 1
-    - _Cutoff: 0.5
-    - _DetailNormalMapScale: 1
-    - _DstBlend: 0
-    - _GlossMapScale: 1
-    - _Glossiness: 0.5
-    - _GlossyReflections: 1
-    - _Metallic: 0
-    - _Mode: 0
-    - _OcclusionStrength: 1
-    - _Parallax: 0.02
-    - _SmoothnessTextureChannel: 0
-    - _SpecularHighlights: 1
-    - _SrcBlend: 1
-    - _UVSec: 0
-    - _ZWrite: 1
-    m_Colors:
-    - _Color: {r: 1, g: 1, b: 1, a: 1}
-    - _EmissionColor: {r: 0, g: 0, b: 0, a: 1}

Assets/Scenes/ImageTracking/UnlitTexture.mat.meta

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