Fixed a serialization issue with scene settings

ScriptableRenderPipeline/Core/CoreRP/Editor/Volume/VolumeProfileFactory.cs

             AssetDatabase.Refresh();
             return profile;
         }
+
+        public static T CreateVolumeComponent<T>(VolumeProfile profile, bool overrides = false, bool saveAsset = true)
+            where T : VolumeComponent
+        {
+            var comp = profile.Add<T>(overrides);
+            AssetDatabase.AddObjectToAsset(comp, profile);
+
+            if (saveAsset)
+            {
+                AssetDatabase.SaveAssets();
+                AssetDatabase.Refresh();
+            }
+
+            return comp;
+        }
     }
 
     class DoCreatePostProcessProfile : EndNameEditAction

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Editor/HDRenderPipelineMenuItems.cs

             Selection.activeObject = sceneSettings;
 
             var profile = VolumeProfileFactory.CreateVolumeProfile(sceneSettings.scene, "Scene Settings");
-            profile.Add<HDShadowSettings>(true);
-            var visualEnv = profile.Add<VisualEnvironment>(true);
+            VolumeProfileFactory.CreateVolumeComponent<HDShadowSettings>(profile, true, false);
+            var visualEnv = VolumeProfileFactory.CreateVolumeComponent<VisualEnvironment>(profile, true, false);
-            profile.Add<ProceduralSky>(true);
-            profile.Add<ExponentialFog>(true);
+            VolumeProfileFactory.CreateVolumeComponent<ProceduralSky>(profile, true, false);
+            VolumeProfileFactory.CreateVolumeComponent<ExponentialFog>(profile, true, true);
 
             var volume = sceneSettings.AddComponent<Volume>();
             volume.isGlobal = true;