CI: add preview builds via CircleCI html build and GHA link redirector

Author: rgommers

Diff for: .circleci/config.yml

@@ -0,0 +1,31 @@
+version: 2
+
+# Aliases to reuse
+_defaults: &defaults
+  docker:
+    # CircleCI maintains a library of pre-built images
+    # documented at https://circleci.com/docs/2.0/circleci-images/
+    - image: cimg/python:3.10.2
+  working_directory: ~/repo
+
+jobs:
+  build_page:
+    <<: *defaults
+    steps:
+      - checkout
+      - attach_workspace:
+          at: ~/
+      - run:
+          name: build docs
+          no_output_timeout: 25m
+          command: |
+            pip install -r requirements.txt
+            sphinx-build -b html -WT --keep-going spec build/draft -d doctrees
+      - store_artifacts:
+          path: build/draft
+
+workflows:
+  version: 2
+  default:
+    jobs:
+      - build_page

Diff for: .github/workflows/preview.yml

@@ -0,0 +1,16 @@
+on: [status]
+jobs:
+  circleci_artifacts_redirector_job:
+    # Don't run Action on forks, and allow skipping CI
+    if: "github.repository == 'data-apis/dataframe-api'"
+    runs-on: ubuntu-latest
+    name: Run CircleCI artifacts redirector
+    steps:
+      - name: GitHub Action step
+        id: step1
+        uses: larsoner/circleci-artifacts-redirector-action@master
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          artifact-path: 0/build/draft/index.html
+          circleci-jobs: build_page
+          job-title: Check the rendered docs here!