Typo in ManagedGit ParentEnumerator.MoveNext causes incorrect behavior and ArgumentOutOfRangeException

[GlebChili]

Implementation of the ParentEnumerator.MoveNext method in ManagedGit contains a small typo, which leads to incorrect behavior and System.ArgumentOutOfRangeException while iterating when number of commit's parents is greater than 2:

Nerdbank.GitVersioning/src/NerdBank.GitVersioning/ManagedGit/GitCommit.cs

Line 167 in 6f656c3

_ => this.owner.AdditionalParents?.Count >= this.position - 2,

A non-strict inequality there should be replaced with a strict one.

I have opened a PR #693 which fixes the typo and adds a corresponding test. I'm testing against a real commit from mono/mono repository: mono/mono@ab39e8a.
It is a quite old commit from the times when merge strategy allowed commits to have three parents.

[AArnott]

Great find. Incidentally, merges still allow more than two parents. I create them occasionally, but not enough apparently to hit this bug myself.