Adjust to interface changes in the vonMises asm

src/one-body-sample.cc

@@ -373,8 +373,9 @@ int main(int argc, char *argv[]) {
       u4 += u4_diff;
 
       { // Compute von Mises stress and write everything to a file
-        auto *displacement =
-            new BasisGridFunction<P1Basis, VectorType>(p1Basis, u4);
+        auto displacement =
+            Dune::make_shared<BasisGridFunction<P1Basis, VectorType> const>(
+                p1Basis, u4);
         VonMisesStressAssembler<GridType> localStressAssembler(E, nu,
                                                                displacement);
         FunctionalAssembler<P0Basis>(p0Basis)