feat: Updates to .NET 9 (#1984)

### Summary

* Bumps to .NET 9 with updated dependencies
* Comparing a value type against null is no longer allowed
* CI/CD now uses the version specified in global.json
* Serialization generator updated to .NET 9 with bug fixes, fixes to turkish language, and parallelization

.github/workflows/create-release.yml

@@ -14,10 +14,10 @@ jobs:
       with:
         fetch-depth: 0 # avoid shallow clone so nbgv can do its work.
         token: ${{ secrets.PERSONAL_ACCESS_TOKEN }}
-    - name: Setup .NET 8
+    - name: Install .NET 9
       uses: actions/setup-dotnet@v4
       with:
-        dotnet-version: 8.0.x
+        global-json-file: global.json
     - name: Install NGBV
       uses: dotnet/nbgv@master
       id: nbgv