Changed HDRI lux step value

com.unity.render-pipelines.high-definition/HDRP/Editor/Sky/HDRISky/HDRISkyEditor.cs

         public void GetUpperHemisphereLuxValue()
         {
             Cubemap hdri = m_hdriSky.value.objectReferenceValue as Cubemap;
-            HDRISky sky = target as HDRISky;
+
+            if (hdri == null)
+                return;
 
             float omegaP = (Mathf.PI * 4) / (6.0f * hdri.width * hdri.width);
             m_IntegrateHDRISkyMaterial.SetTexture(HDShaderIDs._Cubemap, hdri);

com.unity.render-pipelines.high-definition/HDRP/Sky/HDRISky/IntegrateHDRISky.shader

             real GetUpperHemisphereLuxValue(TEXTURECUBE_ARGS(skybox, sampler_skybox), real3 N, uint sampleCount = 16384)
             {
                 float sum = 0.0;
-                float dphi = 0.002;
-                float dtheta = 0.002;
+                float dphi = 0.005;
+                float dtheta = 0.005;
                 for (float phi = 0; phi < 2.0 * PI; phi += dphi)
                 {
                     for (float theta = 0; theta < PI / 2.0; theta += dtheta)