Don't return early after re-running checks after startup grace period

Fixes #7147

(cherry picked from commit 06464d720c0d31c22865629062d6da0911d2a01f)

src/NzbDrone.Core/HealthCheck/HealthCheckService.cs

@@ -148,8 +148,6 @@ public void HandleAsync(IEvent message)
                 }
 
                 _isRunningHealthChecksAfterGracePeriod = false;
-
-                return;
             }
 
             IEventDrivenHealthCheck[] checks;