[NWD][Security] Update Newtonsoft.json dependency in Test package Snyk: https://security.snyk.io/vuln/SNYK-DOTNET-NEWTONSOFTJSON-2774678 Testing: NetCoreTests passed successfuly Part of: b/230278644 Release Notes: no Rollout: no Change-Id: Ic3b083e952e602a3312b13fcaddd65d834ac8fd6