tests: add FreshnessPeriod where MustBeFresh is used

Also, set MustBeFresh in autoconfig-server HubData test,
to reflect the behavior of autoconfig client.

refs #4913

Change-Id: I0af29378630a2208e98ef0913d83668a603e9a88
diff --git a/tests/tools/ndn-autoconfig-server/program.t.cpp b/tests/tools/ndn-autoconfig-server/program.t.cpp
index 4e78bef..cc007ce 100644
--- a/tests/tools/ndn-autoconfig-server/program.t.cpp
+++ b/tests/tools/ndn-autoconfig-server/program.t.cpp
@@ -67,6 +67,7 @@
   this->initialize(options);
 
   Interest interest("/localhop/ndn-autoconf/hub");
+  interest.setMustBeFresh(true);
   face.receive(interest);
   face.processEvents(500_ms);