Create deploy-book.yml

Now update the book on every commit on `master` branch, consider to change it less often by having a `publish` branch.

.github/workflows/deploy-book.yml

@@ -0,0 +1,42 @@
+name: deploy-book
+
+# Only run this when the master branch changes
+on:
+  push:
+    branches:
+    - master
+    # If your git repository has the Jupyter Book within some-subfolder next to
+    # unrelated files, you can make this run only if a file within that specific
+    # folder has been modified.
+    #
+    # paths:
+    # - some-subfolder/**
+
+# This job installs dependencies, builds the book, and pushes it to `gh-pages`
+jobs:
+  deploy-book:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+
+    # Install dependencies
+    - name: Set up Python 3.8
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3.8
+
+    - name: Install dependencies
+      run: |
+        pip install -r docs/requirements.txt
+
+    # Build the book
+    - name: Build the book
+      run: |
+        jupyter-book build --all docs/
+
+    # Push the book's HTML to github-pages
+    - name: GitHub Pages action
+      uses: peaceiris/[email protected]
+      with:
+        github_token: ${{ secrets.GITHUB_TOKEN }}
+        publish_dir: docs/_build/html