Update GitHub Actions and doc paths

Updated the `actions/checkout` action from version 3 to version 4.
Updated the `actions/setup-dotnet` action from version 3 to version 4.
Changed the path for the `docfx` command from `Docs/docfx.json` to `Source/Docs/docfx.json`.
Updated the path for the `actions/upload-pages-artifact` action from `Docs/_site` to `Source/Docs/_site`.

These updates ensure compatibility with newer versions of the actions and reflect a change in the directory structure for the documentation files.

.github/workflows/docfx-publish.yml

@@ -24,20 +24,20 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - name: Dotnet Setup
-      uses: actions/setup-dotnet@v3
+      uses: actions/setup-dotnet@v4
       with:
         dotnet-version: 8.x
 
     - run: dotnet tool update -g docfx
-    - run: docfx Docs/docfx.json
+    - run: docfx Source/Docs/docfx.json
 
     - name: Upload artifact
       uses: actions/upload-pages-artifact@v3
       with:
         # Upload entire site directory
-        path: 'Docs/_site'
+        path: 'Source/Docs/_site'
     - name: Deploy to GitHub Pages
       id: deployment
       uses: actions/deploy-pages@v4