trying to fix doc build

Author: kdubois

.github/workflows/build.yml

@@ -78,6 +78,8 @@ jobs:
       - name: Generate documentation
         working-directory: docs
         run: |
+          sudo apt-get update
+          sudo apt-get install -y libxml2-dev libxslt-dev python3-dev
           pip install pipenv
           pipenv install
           pipenv run mkdocs build --clean