Fixing dependabot issues

Author: gnongsie

cybersource-rest-client-dotnet.nuspec

@@ -11,7 +11,7 @@
     <description>Use this client SDK to Call CyberSource REST API's. This SDK includes generates both HTTP Signature and JWT headers (including authentication headers) for the API requests.</description>
     <releaseNotes>Minor Release.</releaseNotes>
     <dependencies>
-      <dependency id="Newtonsoft.Json" version="11.0.2"></dependency>
+      <dependency id="Newtonsoft.Json" version="13.0.1"></dependency>
       <dependency id="RestSharp" version="106.12.0"></dependency>
       <dependency id="NLog" version="4.5.10"></dependency>
       <dependency id="CyberSource.Authentication" version="0.0.0.15"></dependency>

test/packages.config

@@ -2,5 +2,5 @@
 <packages>
   <package id="NUnit" version="2.6.4" targetFramework="net45" />
   <package id="RestSharp" version="106.12.0" targetFramework="net45" developmentDependency="true" />
-  <package id="Newtonsoft.Json" version="11.0.2" targetFramework="net45" developmentDependency="true" />
+  <package id="Newtonsoft.Json" version="13.0.1" targetFramework="net45" developmentDependency="true" />
 </packages>