Update the health check endpoint route builder extensions to make the endpoint display name configurable.

[CBaud]

Is your feature request related to a problem? Please describe.

In ASP.NET Core 3.0 Preview 3, the health check endpoint route builder extensions specify a common display name ("Health checks") for all health check endpoints.

Describe the solution you'd like

It would be helpful if the extensions allowed the display name to be configurable by the service. For example, a service running on Kubernetes may have two separate health check endpoints for the liveness and readiness probes.

Describe alternatives you've considered

The alternative would be to manually configure the health check endpoints in my service.

[rynowak]

Thanks @CBaud

FYI I'm not sure you saw my follow up PR - we decided to make this part of the builder returned from MapHealthChecks. So this is uniform across all endpoint routing stuff and won't be missed when we add future router-ware. Just mentioning because we ended up not going with your fix. I'm glad that you made the effort and I don't want you to think we don't appreciate it.