tweaking grain range to have a lower minimum range

A range below 0.3 creates visible patterns and a artifacts.

Author: Johannes Deml

PostProcessing/Runtime/Models/GrainModel.cs

@@ -14,7 +14,7 @@ public struct Settings
             [Range(0f, 1f), Tooltip("Grain strength. Higher means more visible grain.")]
             public float intensity;
 
-            [Range(1f, 3f), Tooltip("Grain particle size in \"Filmic\" mode.")]
+            [Range(0.3f, 3f), Tooltip("Grain particle size in \"Filmic\" mode.")]
             public float size;
 
             [Range(0f, 1f), Tooltip("Controls the noisiness response curve based on scene luminance. Lower values mean less noise in dark areas.")]