docs: content is not valid for volumes, replace example with configs instead

[mikran]

"content" is not part of volumes in compose spec. I've updated example to match desired outcome "Here you can see how to add a file with content and a dynamic value that is coming from an environment variable." with configs instead.

[github-actions]

Hi @mikran,

This PR has been automatically closed because it has no description.
Please provide a valid description explaining your changes and reopen the PR.

[mikran]

I've added description, but I don't have access to reopen the PR

[github-actions]

Hi @mikran,

The base branch of this PR has been automatically changed to next.
All contributors must commit changes to the next branch.

A maintainer will review your PR within 5 to 7 business days. Thank you!

[peaklabs-dev]

It's not part of the volumes in compose spec but Coolify has added this custom content option to easily provide content in a file. Do you think it would be better to use configs option from compose instead (in the future)?

[mikran]

I don't know why it was added - but to avoid the confusion I would like to see the (this is not available in a normal docker-compose) comment in it, same as is_directory option before it

[peaklabs-dev]

@mikran It will probably removed in the next major version. For now can you add that comment and maybe add the configs way as another example.

[mikran]

@mikran It will probably removed in the next major version. For now can you add that comment and maybe add the configs way as another example.

I added that