$(GitCommit) does not resolve in first 7 digits of Git Sha, but something else

[HaraldWikeroy]

I added the following to sections to my C# project file:

<PropertyGroup>
    <GitVersion>false</GitVersion> <!-- we'll do our own versioning -->
</PropertyGroup>

<Target Name="PopulateInfo" DependsOnTargets="GitVersion" BeforeTargets="GetAssemblyVersion;GenerateNuspec;GetPackageContents">
    <PropertyGroup>
        <InformationalVersion>4.0.0+$(GitCommit)</InformationalVersion>
    </PropertyGroup>
</Target>

My expectation was then that I would see 4.0.0+[first 7 digits]. Instead, I'm seeing the following, which looks like the first seven bits of the sha, followed by a dot and then the entire SHA. Could anyone help me find what's wrong here: