Fix linux bugreport menu item failure

On Linux/GTK menu items aren't actually created until they are added
to a menu. The recently added bugreport menu item was Enable()d before
adding, which fails on Linux.

Fixes: #11400

chirp/wxui/main.py

@@ -970,11 +970,11 @@ def make_menubar(self):
         self.bug_report_item = wx.MenuItem(
             help_menu, wx.NewId(),
             _('Report or update a bug...'))
-        self.bug_report_item.Enable(False)
         self.Bind(wx.EVT_MENU,
                   functools.partial(bugreport.do_bugreport, self),
                   self.bug_report_item)
         help_menu.Append(self.bug_report_item)
+        self.bug_report_item.Enable(False)
 
         menu_bar = wx.MenuBar()
         menu_bar.Append(file_menu, wx.GetStockLabel(wx.ID_FILE))