Update IGazePinchInteractor.cs

Author: keveleigh

org.mixedrealitytoolkit.core/Interactors/IGazePinchInteractor.cs

@@ -1,15 +1,12 @@
 // Copyright (c) Mixed Reality Toolkit Contributors
 // Licensed under the BSD 3-Clause
 
-using UnityEngine.XR.Interaction.Toolkit.Interactors;
-
 namespace MixedReality.Toolkit
 {
     /// <summary>
     /// An interface that all gaze-pinch-like interactors must implement.
     /// </summary>
     public interface IGazePinchInteractor :
-        IXRInteractionStrengthInteractor,
 #pragma warning disable CS0618 // Type or member is obsolete
         IVariableSelectInteractor
 #pragma warning restore CS0618 // Type or member is obsolete