Make `Validator.VerifyAndUpdate` method to return an error if at least one
of LOCODE-derived attributes is set explicitly. Thus, IR will not confirm
the candidates for the network map who independently set these attributes.
Cover `Validator.VerifyAndUpdate` method with unit tests.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Alexey Vanin
Pavel Karpy
Leonard Lyubich
Alex Vanin
Evgenii Stratonikov