add Sphinx Check (#844)

* add sphinx bot

* source

* typo

* Make a change to the docs (#2)

* Make a change to the docs
* Introduce an error
* Install git before building docs
* Apply suggestions from code review

Co-authored-by: Jirka Borovec <Borda@users.noreply.github.com>

* Update docs/source/apex.rst

* Update docs/source/apex.rst

Co-authored-by: Ammar Askar <ammar_askar@hotmail.com>

.github/workflows/docs-check.yml

@@ -0,0 +1,17 @@
+name: "Docs check"
+# https://github.com/marketplace/actions/sphinx-build
+
+on:
+- pull_request
+
+jobs:
+  docs:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - uses: ammaraskar/sphinx-action@master
+      with:
+        # git is requried to clone the docs theme
+        pre-build-command: "apt-get update -y && apt-get install -y git"
+        docs-folder: "docs/"
+        repo-token: "${{ secrets.GITHUB_TOKEN }}"