server: fix broken /health

[jseldess]

PR: cockroachdb/cockroach#45119

From release notes:

The non-authenticated /health HTTP endpoint was previously exposing the private IP address of the node, which can be privileged information in some deployments. This has been corrected. Deployments using automation to retrieve a node build details and address details should use /_status/details/local instead and use a valid admin authentication cookie. [#45119][#45119] {% comment %}doc{% endcomment %}