[Snyk] Security upgrade Newtonsoft.Json from 11.0.2 to 13.0.1 (#750)
[Snyk] Security upgrade Newtonsoft.Json from 11.0.2 to 13.0.1 (#750)

* fix: src/WireMock.Net/WireMock.Net.csproj to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-DOTNET-NEWTONSOFTJSON-2774678

* Update WireMock.Net.csproj

Co-authored-by: Stef Heyenrath <648de8aede6a202d6746927529bad068288ca732@gmail.com>
WireMock-Net/WireMock.Net