Add benchmark for archetype indexing by handle vs array access vs field direct access

[DrSmugleaf]

BenchmarkDotNet=v0.12.1, OS=Windows 10.0.19045
AMD Ryzen 9 7900X, 1 CPU, 24 logical and 12 physical cores
.NET Core SDK=7.0.101
  [Host]     : .NET Core 7.0.1 (CoreCLR 7.0.122.56804, CoreFX 7.0.122.56804), X64 RyuJIT
  DefaultJob : .NET Core 7.0.1 (CoreCLR 7.0.122.56804, CoreFX 7.0.122.56804), X64 RyuJIT


|          Method |     Array | Element | Handle |     Mean |     Error |    StdDev | Gen 0 | Gen 1 | Gen 2 | Allocated |
|---------------- |---------- |-------- |------- |---------:|----------:|----------:|------:|------:|------:|----------:|
| GetArrayElement | Int32[10] |       5 |    500 | 3.088 ns | 0.0164 ns | 0.0154 ns |     - |     - |     - |         - |
|     GetExisting | Int32[10] |       5 |    500 | 3.060 ns | 0.0234 ns | 0.0208 ns |     - |     - |     - |         - |
|    GetArchetype | Int32[10] |       5 |    500 | 3.478 ns | 0.0159 ns | 0.0148 ns |     - |     - |     - |         -