NewtonSoft serialiser updated but SystemtextJson was not

STJ package still depends on v1.11.0 of the core Ardalis package

This has been outstanding since March

Start by locating the System.Text.Json package project and its dependency declaration for the core Ardalis package. Update the dependency from v1.11.0 to the version used by the NewtonSoft serializer package, then verify that the package builds and its existing tests pass.

Written by the indexing model from the issue text.