Return the password
<include/boost/url/authority_view.hpp>
pct_string_view
encoded_password() const noexcept;
This function returns the password portion of the userinfo as a percent-encoded string.
assert( url_view( "http://jane%2Ddoe:pass@example.com" ).encoded_password() == "pass" );
userinfo = user [ ":" [ password ] ]
user = *( unreserved / pct-encoded / sub-delims )
password = *( unreserved / pct-encoded / sub-delims / ":" )
has_password , has_userinfo , encoded_user , encoded_userinfo , password , user , userinfo .