Stop the timer in console IPC client sample once we don't need it any more.

Stop the timer in console IPC client sample once we don't need it any more.

Under MSW the timer appeared to be flooding the message queue with timer
events faster than we could process them (which seems incredible for the timer
interval of 1 second but still seems to happen), so the idle events were never
generated and the sample didn't work at all.

Now stop the timer once we get a last notification from it to let the program
become idle and run the test function scheduled from the timer handler.

See #11528.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64566 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775