managers: use async_method_call() set PID properties

In sdbusplus::asio::setProperty(), the property value will be wrapped
by std:variant automaticly, it will fail and show `Invalid argument
[generic:22]` error if we pass the property value that has been wrapped
by std::variant into sdbusplus::asio::setProperty().

Because the type of property.second is DbusVariantType, we cannot use
sdbusplus::asio::setProperty() for property setting, so change it back
to use async_method_call().

Tested on Bletchley:
Success PATCH the properties of StepwiseControllers.
```
{
    "Oem": {
        "OpenBmc": {
            "Fan": {
                "StepwiseControllers": {
                    "Test1": {
                        "NegativeHysteresis": 7.0,
                        "PositiveHysteresis": 8.0
                    }
                }
            }
        }
    }
}
```

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I92d9e0d6ffe97fa6ce2905e17497d4d0fffa1d58
diff --git a/redfish-core/lib/managers.hpp b/redfish-core/lib/managers.hpp
index 314099b..38add8b 100644
--- a/redfish-core/lib/managers.hpp
+++ b/redfish-core/lib/managers.hpp
@@ -1591,10 +1591,7 @@
                 {
                     for (const auto& property : output)
                     {
-                        sdbusplus::asio::setProperty(
-                            *crow::connections::systemBus,
-                            "xyz.openbmc_project.EntityManager", path, iface,
-                            property.first, property.second,
+                        crow::connections::systemBus->async_method_call(
                             [response,
                              propertyName{std::string(property.first)}](
                                 const boost::system::error_code& ec) {
@@ -1606,7 +1603,10 @@
                                 return;
                             }
                             messages::success(response->res);
-                        });
+                        },
+                            "xyz.openbmc_project.EntityManager", path,
+                            "org.freedesktop.DBus.Properties", "Set", iface,
+                            property.first, property.second);
                     }
                 }
                 else