fix assertion error in TST TC view

Tst/tst/tc_management.py

@@ -204,13 +204,17 @@ class TcTable(Gtk.Grid):
         # self.attach(self.scrollable_treelist, 0, 1, 8, 10)
         self.attach(self.paned, 0, 1, 8, 10)
 
-        self.paned.add1(self.scrollable_treelist)
+        self.grid = Gtk.Grid()
+        self.paned.add1(self.grid)
+        # self.paned.add1(self.scrollable_treelist)
 
+        self.grid.attach(self.scrollable_treelist, 0, 1, 8, 10)
         self.scrollable_treelist.add(self.treeview)
 
         self.command_entry = Gtk.Entry()
         self.command_entry.set_placeholder_text("<Command Variables>")
-        self.attach_next_to(self.command_entry, self.scrollable_treelist, Gtk.PositionType.BOTTOM, 8, 1)
+        self.command_entry.set_editable(False)
+        self.grid.attach_next_to(self.command_entry, self.scrollable_treelist, Gtk.PositionType.BOTTOM, 8, 1)
 
         self.variable_box = CommandDescriptionBox()
         # self.attach_next_to(self.variable_box, self.command_entry, Gtk.PositionType.BOTTOM, 8, 5)