install mkdocs-include-markdown-plugin for ci

.gitlab-ci.yml

@@ -15,6 +15,7 @@ before_script:
   - pip install pymdown-extensions
   - pip install mkdocs-minify-plugin
   - pip install mkdocs-macros-plugin
+  - pip install mkdocs-include-markdown-plugin
 
 test:
   stage: test