Fix remote harbor healthcheck functionality

The review contain two changes:
The first is adding implementation for HealthCheck in src/pkg/reg/adapter/harbor/v2/adapter.go
The second general issue, in which a change made in src/controller/registry/controller.go by removing the continue inside the loop,
the continue prevent from updating regMgr.Update with the status change

src/controller/registry/controller.go

@@ -232,7 +232,6 @@ func (c *controller) StartRegularHealthCheck(ctx context.Context, closing, done
 				isHealthy, err := c.IsHealthy(ctx, registry)
 				if err != nil {
 					log.Errorf("failed to check health of registry %d: %v", registry.ID, err)
-					continue
 				}
 				status := model.Healthy
 				if !isHealthy {

src/pkg/reg/adapter/harbor/v2/adapter.go

@@ -23,6 +23,7 @@ import (
 	"github.com/goharbor/harbor/src/pkg/reg/adapter/harbor/base"
 	"github.com/goharbor/harbor/src/pkg/reg/filter"
 	"github.com/goharbor/harbor/src/pkg/reg/model"
+	"github.com/goharbor/harbor/src/lib/log"
 )
 
 var _ adp.Adapter = &adapter{}
@@ -144,3 +145,11 @@ func (a *adapter) CanBeMount(digest string) (bool, string, error) {
 	}
 	return true, repository, nil
 }
+
+func (a adapter) HealthCheck() (string, error) {
+	if err := a.Ping(); err != nil {
+		log.Errorf("failed to ping registry %s: %v", a.Registry.URL, err)
+		return model.Unhealthy, nil
+	}
+	return model.Healthy, nil
+}