Docker image :latest not pointing to released version

[tribut]

Checklist

• I am running the latest version. Installing Isso from GitHub from the master branch does not fix my issue
• I have checked the troubleshooting guide
• I have searched the open issues, but my issue has not already been reported

What is not working?

The docker image ghcr.io/isso-comments/isso:latest is apparently updated for every commit. This conflicts with the information in the README, which states:

A Docker image with the latest stable release is provided at ghcr.io/isso-comments/isso:latest

(highlight mine)

[jelmer]

I think if we want to provide a tag like this, we shouldn't call it latest but rather create a separate tag with a clearer name ("release") ?

That said, I think it's good practice to pin a specific release so maybe we should just drop the documentation.

[ix5]

See #1014