tools: switch to Face::getIoContext()

Change-Id: I6be4c682d62e1061af45052d2141b9e5b9e897c5
diff --git a/tools/ndn-autoconfig/procedure.hpp b/tools/ndn-autoconfig/procedure.hpp
index d9513ed..a15b117 100644
--- a/tools/ndn-autoconfig/procedure.hpp
+++ b/tools/ndn-autoconfig/procedure.hpp
@@ -52,15 +52,16 @@
   void
   initialize(const Options& options);
 
-  /** \brief Run HUB discovery procedure once.
+  /**
+   * \brief Run the HUB discovery procedure once.
    */
   void
   runOnce();
 
   boost::asio::io_context&
-  getIoService()
+  getIoContext() const noexcept
   {
-    return m_face.getIoService();
+    return m_face.getIoContext();
   }
 
 private: