docs: update DocFX Github action

Author: anthonyreilly

.github/workflows/build_docs.yml

@@ -50,7 +50,7 @@ jobs:
       run: docfx src/docs/docfx.json
 
     - name: Upload artifact
-      uses: actions/upload-pages-artifact@v4
+      uses: actions/upload-pages-artifact@v3
       with:
         # Upload entire repository
         path: 'src/docs/_site'