Mark EncryptedData encode as unsupported atm

lib/rex/proto/kerberos/model/type/encrypted_data.rb

@@ -28,12 +28,16 @@ module Rex
               when OpenSSL::ASN1::Sequence
                 decode_asn1(input)
               else
-                raise ::RuntimeError, 'Failed to decode Principal Name, invalid input'
+                raise ::RuntimeError, 'Failed to decode EncryptedData Name, invalid input'
               end
 
               self
             end
 
+            def encode
+              raise ::RuntimeError, 'EncryptedData encoding is not supported'
+            end
+
             private
 
             # Decodes a Rex::Proto::Kerberos::Model::Type::EncryptedData from an String