Fix "Main Camera fallback" preference description after recent changes (#284)

Author: gabrieldelacruz

com.unity.visualeffectgraph/Documentation~/VisualEffectPreferences.md

@@ -13,5 +13,5 @@ Visual Effect Graph preferences is a panel in the Unity Preferences window. To a
 | **Verbose Mode for Compilation**        | Enable Verbose logging in Console when Compiling Graphs.     |
 | **Experimental Shader Externalization** | Enable Externalizing Shaders (for Debugging purposes) in the [Visual Effect Graph Asset Inspector](VisualEffectGraphAsset.md) |
 | **Force Compilation in Edition Mode**   | Disables Graph Optimization when Saving Assets (for Debug Purposes Only) |
-| **Main Camera fallback**                | Specifies the camera source for the color and depth buffer that [MainCamera](Operator-MainCamera.md) Operators use when in the editor. The options are:<br/>&#8226; **Prefer Main Camera**: If the Game view is open, Unity uses the main Camera. If the Game view is not open, but the Scene view is, Unity uses the Scene view Camera.<br/>&#8226; **Prefer Scene Camera**: If the Scene view is open, Unity uses the Scene view Camera. If the Scene view is not open, but the Game view is, Unity uses the main Camera.<br/>&#8226; **No Fallback**: Uses the main Camera even if Unity does not render to it. |
+| **Main Camera fallback**                | Specifies the camera source for [MainCamera](Operator-MainCamera.md) Operators and [Blocks](Blocks.md) to use when in the editor. The options are:<br/>&#8226; **Prefer Main Camera**: If the Game view is open, Unity uses the main Camera. If the Game view is not open, but the Scene view is, Unity uses the Scene view Camera.<br/>&#8226; **Prefer Scene Camera**: If the Scene view is open, Unity uses the Scene view Camera. If the Scene view is not open, but the Game view is, Unity uses the main Camera.<br/>&#8226; **No Fallback**: Uses the main Camera even if Unity does not render to it. |
 | **User Systems**                        | Specifies a path to a directory that stores VFX Graph Assets to use as templates for new effects. Any VFX Graph Asset in this folder appears in the visual effect Graph view context menu under **System**. |

com.unity.visualeffectgraph/Editor/GraphView/VFXViewPreference.cs

@@ -153,7 +153,7 @@ public override void OnGUI(string searchContext)
                     }
 #endif
 
-                    m_CameraBuffersFallback = (VFXMainCameraBufferFallback)EditorGUILayout.EnumPopup(new GUIContent("Main Camera fallback", "Specifies the camera source for the color and depth buffer that MainCamera Operators use when in the editor."), m_CameraBuffersFallback);
+                    m_CameraBuffersFallback = (VFXMainCameraBufferFallback)EditorGUILayout.EnumPopup(new GUIContent("Main Camera fallback", "Specifies the camera source for MainCamera Operators and Blocks to use when in the editor."), m_CameraBuffersFallback);
 
                     var userTemplateDirectory = EditorGUILayout.DelayedTextField(new GUIContent("User Systems", "Directory for user-generated VFX templates (e.g. Assets/VFX/Templates)"), VFXResources.defaultResources.userTemplateDirectory);