* Allow health checks to use any DI lifetime
This change allows registered IHealthCheck implementations to use any DI
lifetime. This is necessary for scenarios like using EF which requires a
scope.
The works by having the health check service create a scope for each
time it queries health checks. This scope does not overlap or share
state with other scopes (the request scope) so there is no crosstalk
between processing going on per-request in ASP.NET Core and the health
check operation.
* PR feedback and some logging cleanup
Ryan Nowak
Pranav K
Nate McMaster
Andrew Stanton-Nurse