Refactor getManagedObjects method

Since the getManagedObjects method has been implemented in
dbus_utility and this commit is to integrate all the places where the
GetManagedObjects method is obtained, and use the method in
dbus_utility uniformly.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: Ic13f2bef7b30f805cd3444a75d7df17b031f2eb0
diff --git a/redfish-core/lib/health.hpp b/redfish-core/lib/health.hpp
index ef858a1..c5249f2 100644
--- a/redfish-core/lib/health.hpp
+++ b/redfish-core/lib/health.hpp
@@ -212,7 +212,9 @@
     void getAllStatusAssociations()
     {
         std::shared_ptr<HealthPopulate> self = shared_from_this();
-        crow::connections::systemBus->async_method_call(
+        sdbusplus::message::object_path path("/");
+        dbus::utility::getManagedObjects(
+            "xyz.openbmc_project.ObjectMapper", path,
             [self](const boost::system::error_code& ec,
                    const dbus::utility::ManagedObjectType& resp) {
             if (ec)
@@ -230,9 +232,7 @@
                 }
                 it = self->statuses.erase(it);
             }
-            },
-            "xyz.openbmc_project.ObjectMapper", "/",
-            "org.freedesktop.DBus.ObjectManager", "GetManagedObjects");
+            });
     }
 
     std::shared_ptr<bmcweb::AsyncResp> asyncResp;