Adding missing includes which are necessary for building (facebookresearch#3609)

Summary:
Pull Request resolved: facebookresearch#3609

The current version of Faiss cannot be built due to missing #includes on a test file tests/test_ivf_index.cpp. This is better described in issue facebookresearch#3532.

facebookresearch#3533

Reviewed By: ramilbakhshyiev

Differential Revision: D59314273

fbshipit-source-id: 6ec8bfa973760d0a44bc94ae751b4fc55c4784ef

Author: junjieqi

tests/test_ivf_index.cpp

@@ -6,12 +6,14 @@
  */
 
 #include <omp.h>
+#include <algorithm>
 #include <cstddef>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <map>
 #include <random>
+#include <set>
 
 #include <gtest/gtest.h>