ci: use upload-artifact v4 due to github blocking v3

Author: ssimek

Diff for: .github/workflows/main.yaml

@@ -40,7 +40,7 @@ jobs:
     - name: Package Binary
       run: ./node_modules/vsce/vsce package -o cortex-debug.vsix
     - name: Upload Artifact
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: cortex-debug.vsix
         path: ./cortex-debug.vsix