make scaling for penalty quadratic

src/elasticity/assemble/LagrangeElasticity.hpp

@@ -118,7 +118,7 @@ public:
 
   void Scale (double s) const {
     Material &cellMat = eProblem.GetMaterial();
-    cellMat.ScalePenalty(s);
+    cellMat.ScalePenalty(s*s);
   }
       
 };