Add backup and restore to docker-compose page

[nessor]

Hey guys,

I noticed that there is no article regarding backup in the "docker-compose" section.

First of all the question, would something like that be desired?

I would use the following information in the description, which I found after research:

For backup:
https://community.zammad.org/t/how-to-restore-zammad-backup-in-docker-compose-install/1831/3

For the restore:
zammad/zammad-docker-compose#68 (comment)

[MrGeneration]

Hey,

at least the backup script is not the original script that the rest of installation types use. So this is a potential issue that worsens the current docker situation.

I'm personally quite split on this regard. We officially do not support docker compose and it's changing quite often in very big steps without being synced back to the documentation by the maintainer. I'm simply not able to keep up with the docker stuff.

So I'd say PRs are welcome. However, make sure that its reproducable. Expect heavy time delay on my end due to the nature of topic and my time.