Insert another item in the list control in its unit test.

Insert another item in the list control in its unit test.

For some reason the test fails with a single item in the control when running
on the buildbot slave, check if this is still the case if we add another item
to the control.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65686 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775