Bump Newtonsoft.Json in /src/WebUI/dotnet/WebPortal

Bumps [Newtonsoft.Json](https://github.com/JamesNK/Newtonsoft.Json) from 10.0.2 to 13.0.2.
- [Release notes](https://github.com/JamesNK/Newtonsoft.Json/releases)
- [Commits](https://github.com/JamesNK/Newtonsoft.Json/compare/10.0.2...13.0.2)

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

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

src/WebUI/dotnet/WebPortal/WebPortal.csproj

@@ -43,7 +43,7 @@
     <PackageReference Include="Microsoft.IdentityModel.Clients.ActiveDirectory" Version="3.13.9" />
     <PackageReference Include="Microsoft.VisualStudio.Web.BrowserLink" Version="1.1.0" />
     <PackageReference Include="Microsoft.AspNet.WebApi.Client" Version="5.2.2" />
-    <PackageReference Include="Newtonsoft.Json" Version="10.0.2" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.2" />
     <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="1.1.2" />
     <PackageReference Include="Serilog.Extensions.Logging.File" Version="1.0.1" />
     <PackageReference Include="System.Private.DataContractSerialization" Version="4.3.0" />