Allow waiting on summary page

We previously only went on this page when DONE or in ERROR state. Allow
now to be in any state as we switch to it as soon as possible.

Co-authored-by: Jean-Baptiste Lallement <jean-baptiste@ubuntu.com>

system_setup/ui/views/summary.py

@@ -65,8 +65,6 @@ class SummaryView(BaseView):
                 self.view_error_btn,
                 self.reboot_btn,
                 ]
-        else:
-            raise Exception(state)
         if self.controller.showing:
             self.controller.app.ui.set_header(self.title)
         self._set_buttons(btns)