Merge branch 'branch-0.4.0' into 'branch-0.4.0'

MS-350 remove submodule

See merge request megasearch/milvus!350

Former-commit-id: f3f0f9d0dbdee514a43d10c749bba0847c15005e

cpp/build.sh

@@ -85,6 +85,9 @@ fi
 
 # Knowhere build output path
 KNOWHERE_BUILD_DIR="`pwd`/thirdparty/knowhere/knowhere"
+pushd `pwd`/thirdparty/knowhere
+./build.sh -t ${BUILD_TYPE} -p ${KNOWHERE_BUILD_DIR} ${KNOWHERE_OPTS}
+popd
 
 cd cmake_build