update github actions

Author: westnordost

.github/workflows/deploy-demo.yml

@@ -24,11 +24,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Pages
         uses: actions/configure-pages@v1
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v1
+        uses: actions/upload-pages-artifact@v4
         with:
           # Upload entire repository
           path: 'demo/distribution'

.github/workflows/generate-json.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Set up Python
         uses: actions/setup-python@v4
         with: