try to update metadata only when the type is same as before.

cloudooo/handler/ooo/helper/unoconverter.py

@@ -244,6 +244,7 @@ class UnoConverter(object):
               # BBB: old ERP5 code sends Keywords as a string
               # separated by a whitespace.
               value = tuple(value.split(' '))
+          if isinstance(value, type(current_value)):
             setattr(container, prop, value)
           break
       else: