Install only dg in pages workflow (#6)

Author: jayvdb

.github/workflows/pages.yml

@@ -34,7 +34,7 @@ jobs:
         run: |
           mise settings add idiomatic_version_file_enable_tools "[]"
           mise settings experimental=true
-          mise install
+          mise install "github:decisiongraph/dg"
         env:
           GITHUB_TOKEN: ${{ github.token }}