MAINT: copy contents not directory

Author: mmcky

.github/workflows/publish.yml

@@ -104,7 +104,7 @@ jobs:
           QE_SERVICES_PAT: ${{ secrets.QUANTECON_SERVICES_PAT }}
         run: |
           git clone https://quantecon-services:[email protected]/quantecon/lecture-julia.notebooks
-          cp -r _build/lecture-julia.notebooks/ lecture-julia.notebooks
+          cp -r _build/lecture-julia.notebooks/. lecture-julia.notebooks
           cd lecture-julia.notebooks
           git config user.name "QuantEcon Services"
           git config user.email "[email protected]"