core: slim down `common.hpp`

Change-Id: I875c35147edd2261fbaa24e809c170d5cd9b94d3
diff --git a/daemon/rib/readvertise/readvertised-route.hpp b/daemon/rib/readvertise/readvertised-route.hpp
index bc2d8c1..c4e0ac7 100644
--- a/daemon/rib/readvertise/readvertised-route.hpp
+++ b/daemon/rib/readvertise/readvertised-route.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2023,  Regents of the University of California,
+ * Copyright (c) 2014-2024,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -31,6 +31,8 @@
 #include <ndn-cxx/security/signing-info.hpp>
 #include <ndn-cxx/util/scheduler.hpp>
 
+#include <set>
+
 namespace nfd::rib {
 
 /**
@@ -56,7 +58,7 @@
   mutable ndn::security::SigningInfo signer; ///< signer for commands
   mutable size_t nRibRoutes = 0; ///< number of RIB routes that cause the readvertisement
   mutable time::milliseconds retryDelay = 0_ms; ///< retry interval (not used for refresh)
-  mutable scheduler::ScopedEventId retryEvt; ///< retry or refresh event
+  mutable ndn::scheduler::ScopedEventId retryEvt; ///< retry or refresh event
 };
 
 using ReadvertisedRouteContainer = std::set<ReadvertisedRoute>;