Please specify what versions of Benchmark.net are compatible with the current Expecto release in the README

[sonicbhoc]

BenchmarkDotNet's IConfig interface has changed multiple times over the years, and the latest version pulled in by nuget (0.13.12) is incompatible with expecto. The error message I get is:

System.TypeLoadException: Method 'GetEventProcessors' in type 'BenchmarkConfig' from assembly 'Expecto.BenchmarkDotNet, Version=10.1.0.0, Culture=neutral, PublicKeyToken=null' does not have an implementation.

Turns out that this is a new field added in BenchmarkDotNet v0.13.9.

I would suggest clearly mentioning somewhere visible (like the README) what version of BenchmarkDotNet each version of Expecto is tested against just to make it clear what version of the library works.

[farlee2121]

I could get that reviewed and merged real quick if you'd like to draft up a change.

[sonicbhoc]

I can take a crack at it soon. I am a little swamped right now though.