Fix dynamic toolbar tooltip updates on wxGTK
Fix dynamic toolbar tooltip updates on wxGTK

wxToolbarTool::SetShortHelp() does not refresh the UI (i.e. the
internal native representation) in all ports.

At some point, wxOSX was affected, but since fixed:
https://trac.wxwidgets.org/ticket/12362

wxGTK appears to intentionally take this route
(https://github.com/wxWidgets/wxWidgets/blob833ae03c6a80dea21b775fa871af0f32289e0bd4/src/gtk/toolbar.cpp#L808)
and addressing it there is impractical because we have to support many
wxGTK versions.

Fixed by using wxToolbar::SetToolShortHelp() instead. Other nearby code
already uses this set of functions, so it seems only appropriate.

vslavik/poedit,alexhenrie/poedit,nawawi/poedit,nawawi/poedit,PKRoma/poedit,vslavik/poedit,vslavik/poedit,alexhenrie/poedit,alexhenrie/poedit,PKRoma/poedit,alexhenrie/poedit,alexhenrie/poedit,PKRoma/poedit,nawawi/poedit,PKRoma/poedit,vslavik/poedit,nawawi/poedit,PKRoma/poedit,nawawi/poedit,vslavik/poedit