update identity management fixture

Change-Id: Iba8d816ab77cb1f636d9f670498b50224c252eea
diff --git a/tests/database-fixture.hpp b/tests/database-fixture.hpp
index 28199e9..d737582 100644
--- a/tests/database-fixture.hpp
+++ b/tests/database-fixture.hpp
@@ -40,8 +40,8 @@
 public:
   DatabaseFixture()
   {
-    auto parentDir = boost::filesystem::path(getenv("HOME"));
-    dbDir = parentDir / ".ndncert";
+    boost::filesystem::path parentDir{TMP_TESTS_PATH};
+    dbDir = parentDir / "test-home/.ndncert";
     if (!boost::filesystem::exists(dbDir)) {
       boost::filesystem::create_directory(dbDir);
     }
@@ -52,7 +52,7 @@
     boost::filesystem::remove_all(dbDir);
   }
 
-public:
+protected:
   boost::filesystem::path dbDir;
 };
 
diff --git a/tests/identity-management-fixture.cpp b/tests/identity-management-fixture.cpp
index c780d6e..db99d5a 100644
--- a/tests/identity-management-fixture.cpp
+++ b/tests/identity-management-fixture.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2018 Regents of the University of California.
+ * Copyright (c) 2013-2020 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
diff --git a/tests/identity-management-fixture.hpp b/tests/identity-management-fixture.hpp
index f0125a5..a45e9d0 100644
--- a/tests/identity-management-fixture.hpp
+++ b/tests/identity-management-fixture.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2018 Regents of the University of California.
+ * Copyright (c) 2013-2020 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *