sylva-units: include management.values.yaml in k8s 1.27/1.28 test values

Closes #1551 (closed)

The issue fixed by !2761 (merged) would have been catched if the test values for k8s 1.27/1.28 would have included management.values.yaml (if not, some conditional units are disabled and aren't fully processed).

This MR fixes that.

💡 reviewers, what you see in the diff are additions of symlinks