add new macros that were missing from Metal.hlsl

Assets/ScriptableRenderLoop/ShaderLibrary/API/Metal.hlsl

 
 #define SAMPLE_TEXTURE2D(textureName, samplerName, coord2) textureName.Sample(samplerName, coord2)
 #define SAMPLE_TEXTURE2D_LOD(textureName, samplerName, coord2, lod) textureName.SampleLevel(samplerName, coord2, lod)
+#define SAMPLE_TEXTURE2D_BIAS(textureName, samplerName, coord2, bias) textureName.SampleBias(samplerName, coord2, bias)
+#define SAMPLE_TEXTURE2D_ARRAY_BIAS(textureName, samplerName, coord2, index, bias) textureName.SampleBias(samplerName, float3(coord2, index), bias)
+#define SAMPLE_TEXTURECUBE_BIAS(textureName, samplerName, coord3, bias) textureName.SampleBias(samplerName, coord3, bias)
+#define SAMPLE_TEXTURECUBE_ARRAY_BIAS(textureName, samplerName, coord3, index, bias) textureName.SampleBias(samplerName, float4(coord3, index), bias)
 #define SAMPLE_TEXTURE3D(textureName, samplerName, coord3) textureName.Sample(samplerName, coord3)
 #define SAMPLE_TEXTURE2D_SHADOW(textureName, samplerName, coord3) textureName.SampleCmpLevelZero(samplerName, (coord3).xy, (coord3).z)
 #define SAMPLE_TEXTURE2D_ARRAY_SHADOW(textureName, samplerName, coord3, index) textureName.SampleCmpLevelZero(samplerName, float3((coord3).xy, index), (coord3).z)