!7409 fix dir error when enable download json from gitee

Merge pull request !7409 from liubuyu/bug_fix

cmake/external_libs/json.cmake

@@ -4,14 +4,16 @@ set(nlohmann_json_CFLAGS "-D_FORTIFY_SOURCE=2 -O2")
 if (ENABLE_GITEE)
     set(REQ_URL "https://gitee.com/mirrors/JSON-for-Modern-CPP/repository/archive/v3.6.1.zip")
     set(MD5 "5bda78ce308e6cfcf614dcf1d5ff27a7")
+    set(INCLUDE "./include")
 else()
     set(REQ_URL "https://github.com/nlohmann/json/releases/download/v3.6.1/include.zip")
     set(MD5 "0dc903888211db3a0f170304cd9f3a89")
+    set(INCLUDE "./")
 endif ()
 
 mindspore_add_pkg(nlohmann_json
         VER 3.6.1
-        HEAD_ONLY ./
+        HEAD_ONLY ${INCLUDE}
         URL ${REQ_URL}
         MD5 ${MD5})
 include_directories(${nlohmann_json_INC})