Fix cannot edit grid cell with wxPython 4.1.0 (#2236)

* With wxPython 4.1.0, cannot edit grid cells in windows and linux, to resolve it, removed the useless event listener OnKillFocus

* Revert modifications, only save action is not necessary

Author: jnhyperion

src/robotide/editor/kweditor.py

@@ -219,7 +219,6 @@ def OnSelectCell(self, event):
     def OnKillFocus(self, event):
         self._tooltips.hide()
         self._hide_link_if_necessary()
-        self.save()
         event.Skip()
 
     def _execute(self, command):