minor Py3 issue fixed

https://forum.freecadweb.org/viewtopic.php?f=10&t=30624&p=265892#p265892
fixing as suggested here:
https://hynek.me/articles/hasattr/

src/Mod/Draft/Draft.py

@@ -7390,7 +7390,7 @@ class ViewProviderDraftText:
             if "FontSize" in vobj.PropertiesList:
                 self.font.size = vobj.FontSize.Value
         elif prop == "Justification":
-            if "Justification" in vobj.PropertiesList:
+            if getattr(vobj.PropertiesList, "Justification", None) is not None:
                 from pivy import coin
                 try:
                     if vobj.Justification == "Left":