Bump GitVersion.Tool from 5.6.0 to 5.6.1

Bumps [GitVersion.Tool](https://github.com/GitTools/GitVersion) from 5.6.0 to 5.6.1.
- [Release notes](https://github.com/GitTools/GitVersion/releases)
- [Changelog](https://github.com/GitTools/GitVersion/blob/master/BREAKING_CHANGES.md)
- [Commits](GitTools/GitVersion@5.6.0...5.6.1)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Directory.Build.targets

@@ -11,7 +11,7 @@
         <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
     </ItemGroup>
     <ItemGroup>
-        <PackageReference Update="GitVersion.Tool" Version="5.6.0" />
+        <PackageReference Update="GitVersion.Tool" Version="5.6.1" />
         <PackageReference Update="JetBrains.ReSharper.CommandLineTools" Version="2020.3.2" />
         <PackageReference Update="ReportGenerator" Version="4.8.4" />
         <PackageReference Update="Rocket.Surgery.Nuke" Version="0.14.2" />