[saml models] make key the representable value for KeyValue object
[saml models] make key the representable value for KeyValue object

adieu/authentic2,incuna/authentic,adieu/authentic2,pu239ppy/authentic2,pu239ppy/authentic2,BryceLohr/authentic,pu239ppy/authentic2,pu239ppy/authentic2,BryceLohr/authentic,BryceLohr/authentic,adieu/authentic2,incuna/authentic,incuna/authentic,adieu/authentic2,BryceLohr/authentic,incuna/authentic,incuna/authentic