When the Ingress is updated to a new hostname, the controller does not
currently clean up the old VIPService from control. Fix this up to parse
the ownership comment correctly and write a test to enforce the improved
behaviour
Updates tailscale/corp#24795
Change-Id: I792ae7684807d254bf2d3cc7aa54aa04a582d1f5
Signed-off-by: Tom Proctor <tomhjp@users.noreply.github.com>