Endless loop in CombinedEnumerator.MoveNext()

[rhssiiy]

We have forever loop in DotNetty.Transport.Channels.Groups.CombinedEnumerator.MoveNext() because in .NET 8
an empty ReadOnlyCollection<T> returns a singleton empty enumerator (dotnet/runtime#76097).

So there could be two identical enumerators here:

DotNetty/src/DotNetty.Transport/Channels/Groups/CombinedEnumerator.cs

Lines 12 to 13 in 78c5757

	readonly IEnumerator<T> e1;
	readonly IEnumerator<T> e2;

Which leads to an endless loop here:

DotNetty/src/DotNetty.Transport/Channels/Groups/CombinedEnumerator.cs

Lines 33 to 47 in 78c5757

	for (;;)
	{
	if (this.currentEnumerator.MoveNext())
	{
	return true;
	}
	if (this.currentEnumerator == this.e1)
	{
	this.currentEnumerator = this.e2;
	}
	else
	{
	return false;
	}
	}