Upgrade Seafile Docker

Upgrade from 7.0 to 7.1

Just download the new image, stop the old docker container, modify the Seafile image version in docker-compose.yml to the new version, then start with docker-compose up.

Upgrade from 7.1 to 8.0

Just download the new image, stop the old docker container, modify the Seafile image version in docker-compose.yml to the new version, then start with docker-compose up.