DOC: add the 'domain' option to the docs (#80)

Co-authored-by: Stefan van der Walt <[email protected]>

Author: bsipocz

README.md

@@ -4,7 +4,8 @@ GitHub Action to add a GitHub status link to a CircleCI artifact.
 
 ## Example usage
 
-Sample `.github/workflows/main.yml`:
+Sample `.github/workflows/circleci_redirect.yml`:
+
 
 ```YAML
 on: [status]
@@ -28,6 +29,7 @@ jobs:
           artifact-path: 0/test_artifacts/root_artifact.md
           circleci-jobs: build_doc
           job-title: Check the rendered docs here!
+          domain:
       - name: Check the URL
         if: github.event.status != 'pending'
         run: |
@@ -57,7 +59,10 @@ jobs:
 - The `job-title` corresponds to the name of the action job as it will appear
   on github. It is **not** the circle-ci job you want the artifacts for
   (this is `circleci-jobs`). This field is optional.
-- The action has an outtput ``url`` that you can use in downstream steps, but
+- Use `domain` to set where the CircleCI artifacts are hosted. It defaults to CircleCI, but the
+  [Scientific Python CircleCI proxy](https://github.com/scientific-python/circleci-proxy) can be set, too,
+  as it addresses some routing issues for mystmd generated outputs.
+- The action has an output `url` that you can use in downstream steps, but
   this URL will only point to a valid artifact once the job is complete, i.e.,
   `github.event.status` is either `'success'`, `'fail'`, or (maybe) `'error'`,
   not `'pending'`.