Fix #147559: performance regression due to unnecessary geometry copy

The geometry was copied later on when it was modified because there was still a
reference to it in the modifier. Since this uses implicit sharing, if there is
more than one reference, the data has to be copied before it can be modified.

Pull Request: https://projects.blender.org/blender/blender/pulls/147644

source/blender/nodes/intern/geometry_nodes_execute.cc

@@ -875,7 +875,7 @@ bke::GeometrySet execute_geometry_nodes_on_geometry(const bNodeTree &btree,
     const eNodeSocketDatatype socket_type = typeinfo ? typeinfo->type : SOCK_CUSTOM;
     if (socket_type == SOCK_GEOMETRY && i == 0) {
       bke::SocketValueVariant &value = scope.construct<bke::SocketValueVariant>();
-      value.set(input_geometry);
+      value.set(std::move(input_geometry));
       param_inputs[function.inputs.main[0]] = &value;
       continue;
     }