Updated system.text.json to ver 8.0.5 so it is compliant with security (#929)

Co-authored-by: Badrish Chandramouli <badrishc@microsoft.com>

Author: darrenge

cs/remote/samples/FixedLenServer/FixedLenServer.csproj

@@ -30,6 +30,7 @@
     <PackageReference Include="Microsoft.Extensions.Logging" Version="7.0.0" />
     <PackageReference Include="Microsoft.Extensions.Logging.Configuration" Version="7.0.0" />
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="7.0.0" />
+    <PackageReference Include="System.Text.Json" Version="8.0.5" />
   </ItemGroup>
 
   <ItemGroup>

cs/remote/samples/VarLenServer/VarLenServer.csproj

@@ -27,6 +27,7 @@
 		<PackageReference Include="Microsoft.Extensions.Logging.Configuration" Version="7.0.0" />
 		<PackageReference Include="Microsoft.Extensions.Logging.Console" Version="7.0.0" />
 		<PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="7.0.0" />
+		<PackageReference Include="System.Text.Json" Version="8.0.5" />
 	</ItemGroup>
 
 	<ItemGroup>