add a mirror for the pdf doc (#572)

Author: csukuangfj

.github/workflows/build-doc.yml

@@ -107,6 +107,15 @@ jobs:
               ls -lh sherpa.pdf
               cp -v sherpa.pdf ../html/
 
+      - name: Release sherpa.pdf
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push'
+        uses: svenstaro/upload-release-action@v2
+        with:
+          file_glob: true
+          overwrite: true
+          file: ./docs/build/html/sherpa.pdf
+          tag: doc
+
       - name: Deploy
         uses: peaceiris/actions-gh-pages@v3
         with:

docs/source/pdf.rst

@@ -11,6 +11,12 @@ Please download it from the following address:
 
   `<https://k2-fsa.github.io/sherpa/sherpa.pdf>`_
 
+.. note::
+
+   For Chinese users, you can use the following mirror:
+
+      `<https://hub.nuaa.cf/k2-fsa/sherpa/releases/download/doc/sherpa.pdf>`_
+
 Please always download the latest version.
 
 The pdf file is updated automagically whenever the doc is changed.