Fix a regression in the tessellation code

ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitDataMeshModification.hlsl

     if (_TessellationFactorTriangleSize > 0.0)
     {
         // return a value between 0 and 1
-        edgeTessFactors *= GetScreenSpaceTessFactor( p0, p1, p2, UNITY_MATRIX_VP, _ScreenSize, _TessellationFactorTriangleSize); // Use primary camera view
+        // Warning: '_ViewProjMatrix' is not the same as UNITY_MATRIX_VP for shadow views!
+        edgeTessFactors *= GetScreenSpaceTessFactor( p0, p1, p2, _ViewProjMatrix, _ScreenSize, _TessellationFactorTriangleSize); // Use primary camera view
     }
 
     // Distance based tessellation