utils: restart: Fix restart bug

bc89289f48ce5e1c8e5c66e657a176a0cd881d39 introduced a regression in the
type signature of the RestartUnit call. The "replace" argument was
accidentally deleted.

Change-Id: I44313997b8b72b7163ad8b43ed2b45a01cb54e44
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/phosphor-rsyslog-config/utils.hpp b/phosphor-rsyslog-config/utils.hpp
index 30799cd..f5df8ae 100644
--- a/phosphor-rsyslog-config/utils.hpp
+++ b/phosphor-rsyslog-config/utils.hpp
@@ -28,7 +28,7 @@
     {
         auto method = bus.new_method_call(SYSTEMD_BUSNAME, SYSTEMD_PATH,
                                           SYSTEMD_INTERFACE, "RestartUnit");
-        method.append(service);
+        method.append(service, "replace");
         bus.call_noreply(method);
     }
 }