Add a `show-components` property under `management.endpoint.health` and
`management.endpoint.health.group.<name>` that can be used to change
when components are displayed.

Prior to this commit it was only possible to set `show-details` which
offered an "all or nothing" approach to the resulting JSON. The new
switch allows component information to be displayed whilst still hiding
potentially sensitive details returned from the actual `HealthIndicator`.

Closes gh-15076