Implement DNS platform service

[ValentinGerlach]

Understand the Task

Description

Depends on #229 and #58.

Implement a DNS platform service that:

• runs etcd in a docker container (or the platform cluster)
• runs coredns in a docker container (or the platform cluster) and configures it to read from etcd
• installs external-dns on the platform and workload clusters and configures it to write to etcd
• modify the kind coredns config to point the openmcp.internal DNS zone to the local DNS server

Any further valuable resources.

No response

What is required to accept the Task as done.

Done Criteria

• ...
• Code has been reviewed by other team members
• Internal technical Documentation created/updated
• New / changed code is documented
• Unit Tests created for new code or existing Unit Tests updated
• Integration Test Suite updated
• Enduser Documentation updated (if applicable)
• Successful demonstration in Review

[In-Ko]

Not sure why this task exists, as we have the parent #95 which seems like exactly the same.
I suggest we close this one @ValentinGerlach

[ValentinGerlach]

I guess we intended to use #95 as an epic and this one as the actual implementation task

[In-Ko]

Progress on actual implementation is mentioned in #95.
Only thing left is the presentation in the review. So I guess after that we can close both #95 and this task here (#230)