Add readme

.github/workflows/doc.yml

@@ -31,7 +31,7 @@ jobs:
         shell: bash
         run: |
           apt update
-          apt install -y -qq --no-install-recommends enchant-2
+          apt install -y -qq --no-install-recommends enchant-2 git
           pip install -r docs/requirements.txt
           sphinx-build -b linkcheck ./docs _build
           sphinx-build -b spelling ./docs _build