Fixed ShadowsTest scene directional light parameters (was MSM instead of PCF)

SampleScenes/HDTest/ShadowsTest.unity

   - 0.285
   - 0
   - 0
-  shadowAlgorithm: 3
-  shadowVariant: 0
+  shadowAlgorithm: 0
+  shadowVariant: 4
-    format: 24
-    data: 5839b43d000000000bd7233c02000000
+    format: 4
+    data: 99bb163b0000803f
   shadowDatas:
   - format: 4
     data: 99bb163b0000803f