running time of gs_design_wlr example is > 5s

[LittleBeannie]

To solve notes listing in #490.

[jdblischak]

So the NOTE is only for examples that take longer than 10 seconds? Do I understand correctly? Because we are still getting examples that take more than 5 seconds, eg from ubuntu-latest with R devel

* checking examples ... [28s/26s] OK
Examples with CPU (user + system) or elapsed time > 5s
               user system elapsed
gs_update_ahr 5.547  0.015   4.549
gs_design_wlr 5.220  0.008   4.529

[jdblischak]

Approved assuming that CRAN accepts examples that take more than 5 seconds but less than 10