Create file named .drone.yml and paste:

---
kind: pipeline
type: docker
name: build
steps:
- name: build
  image: squidfunk/mkdocs-material:7.1.9
  volumes:
  - name: site
    path: /site
  commands:
  - /usr/local/bin/python -m pip install --upgrade pip
  - pip install -U -r ./requirements.txt
  - mkdocs build
  - cp -r site/ /site
  - chmod -R 777 /site
volumes:
- name: site
  host:
    path: /mkdocswiki

Replace path: /mkdocswiki with your real path eg: /home/user/docker/mkdocswiki