Fix duplicated test name in Perf.TypeName and update validation

[caaavik-msft]

Due to how the FullNameProvider works, the Dictionary<string, bool>[] and Dictionary<List<int[]>[,], List<int?[][][,]>>[] arguments were both being converted to the string System.Collections.Generic.Dictionary`2[]. Patching this in BenchmarkDotNet would cause too many test names to change, and this is the only case in this repo that there is a duplicate full name, so we can address it by wrapping the type and overriding the ToString.

The display names that I have put here ensure that the test names remain the same as they were before, with only the Dictionary<List<int[]>[,], List<int?[][][,]>>[] case now being converted to typeof(System.Collections.Generic.Dictionary`2[]) (COMPLEX) to differentiate it from the simpler case.

I have also updated the validators to ensure this doesn't happen again.

[caaavik-msft]

@adamsitnik As you had originally added this benchmark, are you able to confirm that the changes to the benchmark by using a wrapper type are acceptable and that adding the property lookup should have a negligible impact on the performance measurement?

[LoopedBard3]

Looks good.

[DrewScoggins]

@caaavik-msft We should probably go ahead and merge this, yeah? Also did we do work on the reporting side to coalesce the results into one trend?

[caaavik-msft]

@caaavik-msft We should probably go ahead and merge this, yeah? Also did we do work on the reporting side to coalesce the results into one trend?

Ah yes, we can merge it, although I don't think there will be a way to fix this on the reporting side, we have no way of knowing which test result came from which, but it will be fixed from now on. We may get a perf regression from this now that the test will stabilise on one case rather than being random