MS-484 1. update faiss version 2. idmap add search config

Former-commit-id: e9b2131870e0a011a94c6cd2fed8166d9ebd80a5

cpp/src/core/cmake/ThirdPartyPackages.cmake

@@ -261,7 +261,7 @@ else()
     message(STATUS ${FAISS_SOURCE_URL})
 endif()
 # set(FAISS_MD5 "a589663865a8558205533c8ac414278c")
-set(FAISS_MD5 "31167ecbd1903fec600dc4ac00b9be9e")
+set(FAISS_MD5 "57da9c4f599cc8fa4260488b1c96e1cc")
 
 if(DEFINED ENV{KNOWHERE_ARROW_URL})
     set(ARROW_SOURCE_URL "$ENV{KNOWHERE_ARROW_URL}")

cpp/src/core/src/knowhere/index/vector_index/idmap.cpp

@@ -39,6 +39,9 @@ DatasetPtr IDMAP::Search(const DatasetPtr &dataset, const Config &config) {
     }
 
     auto k = config["k"].as<size_t>();
+    auto metric_type = config["metric_type"].as_string() == "L2" ?
+                       faiss::METRIC_L2 : faiss::METRIC_INNER_PRODUCT;
+    index_->metric_type = metric_type;
 
     GETTENSOR(dataset)