NNS-contract Resolve return types

[masterSplinter01]

Method of nns-contract Resolve returns []string
https://github.com/nspcc-dev/neofs-contract/blob/master/nns/nns_contract.go#L444

// Resolve resolves given name (not more then three redirects are allowed).
func Resolve(name string, typ RecordType) []string {
	ctx := storage.GetReadOnlyContext()
	return resolve(ctx, nil, name, typ, 2)
}

Neo-go wrapper Resolve requires one string
https://github.com/nspcc-dev/neo-go/blob/master/pkg/rpcclient/nns/contract.go#L59

// Resolve resolves the given record type for the given domain (with no more
// than three redirects).
func (c *ContractReader) Resolve(name string, typ RecordType) (string, error) {
	return unwrap.UTF8String(c.invoker.Call(c.hash, "resolve", name, int64(typ)))
}

Comment to `unwrap.UTF8String(...)

// UTF8String expects correct execution (HALT state) with a single stack item
// returned. A string is extracted from this item and checked for UTF-8
// correctness, valid strings are then returned.

Is it sure it is valid?

[roman-khimov]

It's made to be compatible with the mainnet NNS: https://github.com/neo-project/non-native-contracts/blob/8d72b92e5e5705d763232bcc24784ced0fb8fc87/src/NameService/NameService.cs#L400

I don't think we can have NeoFS version of NNS right in the NeoGo, it'll have wrappers in neofs-contracts.

[AnnaShaleva]

Actually, #2693, #2687 and nspcc-dev/neofs-contract#266 are about to change this and unify the NNS implementation through the neofs-contract and neo-go.

[roman-khimov]

They solve a bit different problem. NeoGo must be compatible with the mainnet NNS.