Bump Newtonsoft.Json from 12.0.3 to 13.0.1 in /Gu.Units.Generator

Bumps [Newtonsoft.Json](https://github.com/JamesNK/Newtonsoft.Json) from 12.0.3 to 13.0.1.
- [Release notes](https://github.com/JamesNK/Newtonsoft.Json/releases)
- [Commits](JamesNK/Newtonsoft.Json@12.0.3...13.0.1)

---
updated-dependencies:
- dependency-name: Newtonsoft.Json
  dependency-type: direct:production
...

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

Author: dependabot[bot]

Gu.Units.Generator/Gu.Units.Generator.csproj

@@ -37,7 +37,7 @@
     <PackageReference Include="IDisposableAnalyzers" Version="4.0.2" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Scripting" Version="4.0.1" />
     <PackageReference Include="Microsoft.VisualStudio.Threading.Analyzers" Version="17.4.27" PrivateAssets="all" />
-    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
     <PackageReference Include="PropertyChangedAnalyzers" Version="4.0.0" PrivateAssets="all" />
     <PackageReference Include="ReflectionAnalyzers" Version="0.3.1" PrivateAssets="all" />
     <PackageReference Include="StyleCop.Analyzers" Version="1.2.0-beta.435" PrivateAssets="all" />