following docs for prod docker without specifying APP_VERSION will now get latest version as docs say

[AnouarTouati]

The docs here highly encourage not letting APP_VERSION empty as it will get the latest version.

But that is not the case, it is hard coded to v6.1.4 in the .env.docker file and if the version number is removed it will still not get the latest version as docker-compose.yml falls back to v7.0.11.

So this change will allow the user to put a specific version or leave it empty to get the latest version.

[welcome]

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[what-the-diff]

PR Summary

• Application Version Update
  The application version information, which was previously specified as a particular value (v7.0.11), has been cleared. This allows for more flexibility in handling updates.

• Docker Image Tag Modification
  The Docker image tag, which decides the version of the Docker image to be deployed, has been switched from a fixed version number (v7.0.11) to "latest". This means that whenever the system is run, it will automatically use the most recent version of the Docker image.

[AnouarTouati]

I split the commits from this PR into three smaller PRs #16009 #16010 #16011 so I am closing this one.