iwyu: Cleanup include headers

Triggered iwyu and add/remove used headers.

Change-Id: Iadbdb459563b3c89baf2d56f90a540342d020cd5
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/subprojects/ncsid/test/iface_test.cpp b/subprojects/ncsid/test/iface_test.cpp
index 267194c..2ae340a 100644
--- a/subprojects/ncsid/test/iface_test.cpp
+++ b/subprojects/ncsid/test/iface_test.cpp
@@ -14,6 +14,9 @@
 
 #include "net_iface_mock.h"
 
+#include <memory>
+
+#include "gtest/gtest.h"
 #include <gtest/gtest.h>
 
 TEST(TestIFace, TestGetIndex)