Update vr_controller_interaction_behavior.hpp to satisfy cppcheck

demos/combustion_demo/src/vr_controller_interaction_behavior.hpp

@@ -52,7 +52,7 @@ class VRControllerInteractionBehavior : public phx::Behavior {
  private:
   phx::Transform* target_ = nullptr;
   bool is_grabbed_ = false;
-  int release_delay_;
+  int release_delay_ = 0;
 };
 
 #endif  // DEMOS_COMBUSTION_DEMO_SRC_VR_CONTROLLER_INTERACTION_BEHAVIOR_HPP_