Fix documentation asset paths for custom domain

Author: rsgalloway

.github/workflows/pages.yml

@@ -29,8 +29,8 @@ jobs:
       - name: Generate Jekyll source
         run: >-
           mkpages build docs --output .mkpages
-          --url "https://subforkdev.github.io"
-          --baseurl "/subfork-python"
+          --url "https://python.subfork.com"
+          --baseurl ""
       - name: Build site
         uses: actions/jekyll-build-pages@v1
         with:

CONTRIBUTING.md

@@ -59,9 +59,3 @@ python -m pip install -e '.[docs]'
 mkpages build docs --output .mkpages
 mkpages preview docs/
 ```
-
-The Pages workflow builds pull requests and deploys `master`. In repository
-**Settings → Pages**, select **GitHub Actions** as the source. The initial site
-URL is `https://subforkdev.github.io/subfork-python/`; the workflow supplies its
-`--url` and `--baseurl` options. Update those if a custom domain is configured.
-Preview serves the documentation at `http://127.0.0.1:4000/`.