Bump NuGet.ProjectModel from 6.13.1 to 6.13.2 (#359)

Bumps [NuGet.ProjectModel](https://github.com/NuGet/NuGet.Client) from 6.13.1 to 6.13.2.
- [Release notes](https://github.com/NuGet/NuGet.Client/releases)
- [Commits](https://github.com/NuGet/NuGet.Client/commits)

---
updated-dependencies:
- dependency-name: NuGet.ProjectModel
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

src/Directory.Build.props

@@ -21,7 +21,7 @@
     <XunitVersion>2.9.3</XunitVersion>
     <TestSdkVersion>17.13.0</TestSdkVersion>
     <RoslynVersion>4.13.0</RoslynVersion>
-    <NugetVersion>6.13.1</NugetVersion>
+    <NugetVersion>6.13.2</NugetVersion>
   </PropertyGroup>
   <ItemGroup>
     <None Include="$(MSBuildThisFileDirectory)\..\README.md" Pack="true" Visible="false" PackagePath="\" />