Do not generate `dco-merge-queue.yml` for private repos

[daniel-zullo-frequenz]

What's needed?

Merge queues might not be available for private repos where an enterprise plan is needed

Proposed solution

dco-merge-queue.yml should not be generated for private repos if merge queues are not available

Use cases

No response

Alternatives and workarounds

No response

Additional context

No response

[llucax]

I would like to add more options to how to generate the templates to enabled/disable features individually, like use_merge_queues or support_arm, then we could have a predefined set of defaults per type of repo (lib, actor, etc.) and repo visibility (private, public). But it is a dream, not sure if I will ever have enough time to do it :D