Remove redundant Initialize() on TestUtils

[OnedgeLee]

libplanet/Libplanet.Tests/TestUtils.cs

Lines 429 to 442 in f3d6674

	txs.AddRange(
	validatorSet.Validators.Select(
	validator => Transaction.Create(
	nonce++,
	GenesisProposer,
	null,
	actions: new IAction[]
	{
	new Initialize(
	validatorSet: validatorSet,
	states: ImmutableDictionary.Create<Address, IValue>()),
	}.Select(x => x.PlainValue),
	timestamp: DateTimeOffset.MinValue)));
	txs = txs.OrderBy(tx => tx.Id).ToList();

Action Initialize() updates validator set of IWorld with given parameter validatorSet.
So above code, that iterates validatorSet, is redundant.
(Initialize() only needs to be called once.)