Fixing test for invalid grid

src/Grid/Iterators/grid_dist_id_iterators_unit_tests.hpp

@@ -309,6 +309,9 @@ void Test3D_decskinit(const Box<3,float> & domain, long int k)
 			sz[1] = k;
 			sz[2] = k;
 
+			if (k <= 9)
+				continue;
+
 			// factor
 			float factor = pow(create_vcluster().getProcessingUnits()/2.0f,1.0f/3.0f);