bump upload-artifact action to v4

Author: jjw24

.github/workflows/build_publish.yml

@@ -23,7 +23,7 @@ jobs:
       run: dotnet build --no-restore -c Release
 
     - name: Upload Artifact
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v4
       with:
         name: ChefKeys
         path: Output/Release/