Refactor healthchecks service mapping to support filtering on check

[JamesNK]

Fixes #2141

• Previously, all health checks were run when Check was called, and then they were filtered. This PR changes the filter to happen before health checks are run. Now health checks can be selectly run depending on Check's service name argument.
• Previous health result filtering is now obsolete. The new predicate is based on the information available when a health check is registered (its name and tags).
• Add some logging to the health check publisher.

API changes:

namespace Grpc.AspNetCore.HealthChecks;

+public sealed class HealthCheckMapContext
+{
+   public HealthCheckMapContext(string name, IEnumerable<string> tags);
+   public string Name { get; }
+   public IEnumerable<string> Tags { get; }
+}

+[Obsolete($"HealthResult is obsolete and will be removed in a future release. Use {nameof(HealthCheckMapContext)} instead.")]
public sealed class HealthResult
{
    public HealthResult(string name, IEnumerable<string> tags, HealthStatus status, string? description, TimeSpan duration, Exception? exception, IReadOnlyDictionary<string, object> data);
    public string Name { get; }
    public IEnumerable<string> Tags { get; }
    public HealthStatus Status { get; }
    public string? Description { get; }
    public IReadOnlyDictionary<string, object> Data { get; }
    public Exception? Exception { get; }
    public TimeSpan Duration { get; }
}

public sealed class ServiceMapping
{
+   [Obsolete("This constructor is obsolete and will be removed in the future. Use ServiceMapping(string name, Func<HealthCheckRegistration, bool> predicate) to map service names to .NET health checks.")]
    public ServiceMapping(string name, Func<HealthResult, bool> predicate);
+   public ServiceMapping(string name, Func<HealthCheckMapContext, bool> predicate);
+   public Func<HealthCheckMapContext, bool>? HealthCheckPredicate { get; }
+   [Obsolete($"This member is obsolete and will be removed in the future. Use {nameof(HealthCheckPredicate)} to map service names to .NET health checks.")]
    public Func<HealthResult, bool>? Predicate { get; }
}

-public sealed class ServiceMappingCollection : IEnumerable<ServiceMapping>
+public sealed class ServiceMappingCollection : ICollection<ServiceMapping>
{
+   [Obsolete("This method is obsolete and will be removed in the future. Use Map(string name, Func<HealthCheckRegistration, bool> predicate) to map service names to .NET health checks.")]
    public void MapService(string name, Func<HealthResult, bool> predicate);
+   public void Map(string name, Func<HealthCheckMapContext, bool> predicate);
}

Usage:

builder.Services.AddGrpcHealthChecks(o =>
{
    o.Services.Map("greet.Greeter", c => c.Tags.Contains("greeter"));
    o.Services.Map("count.Counter", c => c.Tags.Contains("counter"));
});

[JamesNK]

@gfoidl I've simplified the code in the area you commented on. The publisher runs every couple of seconds so I just want to keep it simple.

[gfoidl]

Yep, looks better now 😄
Thanks!

[mgravell]

LGTM; my only comment was something I then deleted