Use a full copy of the book instead of symlink

.github/workflows/build.yml

@@ -586,6 +586,8 @@ jobs:
           stable=$(git tag | grep "^v" | grep -v "-" | tail -n 1 | cut -c2-4)
           vers=( 0.5.x 0.4.x  )
 
+          echo "Stable version: $stable"
+
           # Create directories
           td=$(mktemp -d)
           mkdir -p $td/$devver/book/
@@ -630,8 +632,8 @@ jobs:
               rm -rf $src
           done
 
-          # Create alias for the stable release
-          ln -s $stable $td/stable
+          # Copy the stable book to the stable alias
+          cp -r $td/$stable $td/stable
 
           # Forward CNAME file
           cp CNAME $td/