added benchmark for VirtualPathContainer resolution

[Aaronontheweb]

designed to help measure how quickly we can resolve a temporary actor upon deserialization

[Aaronontheweb]

Forgot to add baseline numbers for this:

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.19041.1165 (2004/May2020Update/20H1)
AMD Ryzen 7 1700, 1 CPU, 16 logical and 8 physical cores
.NET SDK=5.0.302
  [Host]     : .NET Core 3.1.17 (CoreCLR 4.700.21.31506, CoreFX 4.700.21.31502), X64 RyuJIT
  DefaultJob : .NET Core 3.1.17 (CoreCLR 4.700.21.31506, CoreFX 4.700.21.31502), X64 RyuJIT

Method	Mean	Error	StdDev	Gen 0	Allocated
ResolveChild	66.71 ns	0.048 ns	0.040 ns	-	-
Resolve3DeepChildRepointableActorRef	540.70 ns	1.754 ns	1.555 ns	0.0324	136 B
Resolve3DeepChildLocalActorRef	368.26 ns	1.574 ns	1.472 ns	0.0095	40 B
ResolveVirtualPathContainer	93.03 ns	0.532 ns	0.471 ns	0.0305	128 B