tests: IdentityManagementFixture no longer derives from BaseFixture

Also rename it to KeyChainFixture

Refs: #4528
Change-Id: Id86f4affc9c4c9ae159912430cc3e78557bf1ac2
diff --git a/tests/daemon/rib/readvertise/readvertise.t.cpp b/tests/daemon/rib/readvertise/readvertise.t.cpp
index d2d8bb2..15cc105 100644
--- a/tests/daemon/rib/readvertise/readvertise.t.cpp
+++ b/tests/daemon/rib/readvertise/readvertise.t.cpp
@@ -25,9 +25,10 @@
 
 #include "rib/readvertise/readvertise.hpp"
 
-#include "tests/identity-management-fixture.hpp"
+#include "tests/key-chain-fixture.hpp"
 
 #include <ndn-cxx/util/dummy-client-face.hpp>
+
 #include <boost/range/adaptor/transformed.hpp>
 #include <boost/range/algorithm/copy.hpp>
 
@@ -110,7 +111,7 @@
   std::vector<HistoryEntry> withdrawHistory;
 };
 
-class ReadvertiseFixture : public IdentityManagementTimeFixture
+class ReadvertiseFixture : public UnitTestTimeFixture, public KeyChainFixture
 {
 public:
   ReadvertiseFixture()