use latest actions (#8)

Author: mrabine

.github/workflows/build.yml

@@ -36,15 +36,15 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6.0.2
         with:
           submodules: recursive
 
       - name: Build
         run: hugo --minify
 
       - name: Upload to GitHub
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7.0.0
         with:
           name: join-www
           path: public/