Fix nan errors when using VehicleBody

scene/3d/vehicle_body_3d.cpp

@@ -366,6 +366,7 @@ VehicleWheel3D::VehicleWheel3D() {
 	m_suspensionRelativeVelocity = 0;
 	m_clippedInvContactDotSuspension = 1.0;
 	m_raycastInfo.m_isInContact = false;
+	m_raycastInfo.m_suspensionLength = 0.0;
 
 	body = nullptr;
 }