Bump GitVersion.Tool from 5.3.7 to 5.5.0 (#399)

Bumps [GitVersion.Tool](https://github.com/GitTools/GitVersion) from 5.3.7 to 5.5.0.
- [Release notes](https://github.com/GitTools/GitVersion/releases)
- [Changelog](https://github.com/GitTools/GitVersion/blob/master/BREAKING_CHANGES.md)
- [Commits](https://github.com/GitTools/GitVersion/commits)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Build.targets

@@ -8,7 +8,7 @@
     <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Update="GitVersion.Tool" Version="5.3.7" />
+    <PackageReference Update="GitVersion.Tool" Version="5.5.0" />
     <PackageReference Update="JetBrains.ReSharper.CommandLineTools" Version="2020.2.4" />
     <PackageReference Update="ReportGenerator" Version="4.7.1" />
     <PackageReference Update="Rocket.Surgery.Nuke" Version="0.14.0-beta.10" />