Remove nlohmann brace initialization

There's a few last places (outside of tests) where we still use
nlohmann brace initialization.  Per the transforms we've been doing,
move these to constructing the objects explicitly, using operator[],
nlohmann::object_t and nlohmann::array_t.  Theses were found by manual
inspection grepping for all uses of nlohmann::json.

This is done to reduce binary size and reduce the number of intermediate
objects being constructed.  This commit saves a trivial amount of size
(~4KB, Half a percent of total) and in addition but makes our
construction consistent.

Tested:
Redfish service validator passes.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I7478479a9fdc41b254eef325002d413c1fb411a0
diff --git a/redfish-core/lib/task.hpp b/redfish-core/lib/task.hpp
index b40d522..fe3b990 100644
--- a/redfish-core/lib/task.hpp
+++ b/redfish-core/lib/task.hpp
@@ -448,9 +448,10 @@
             {
                 continue; // shouldn't be possible
             }
-            members.emplace_back(
-                nlohmann::json{{"@odata.id", "/redfish/v1/TaskService/Tasks/" +
-                                                 std::to_string(task->index)}});
+            nlohmann::json::object_t member;
+            member["@odata.id"] =
+                "redfish/v1/TaskService/Tasks/" + std::to_string(task->index);
+            members.emplace_back(std::move(member));
         }
         });
 }