clang-error: fix clang-diagnostic-defaulted-function-deleted error

The clang-diagnostic-defaulted-function-deleted error is generated when
explicitly defaulted move assignment operator is implicitly deleted.
This commit fixes those errors.

Change-Id: Id62b89eb3b58b819799194be91516f7c5e9cadc6
Signed-off-by: Pavithra Barithaya <pavithrabarithaya07@gmail.com>
diff --git a/item_updater_helper.hpp b/item_updater_helper.hpp
index 81d66d9..728af96 100644
--- a/item_updater_helper.hpp
+++ b/item_updater_helper.hpp
@@ -18,7 +18,7 @@
     Helper(const Helper&) = delete;
     Helper& operator=(const Helper&) = delete;
     Helper(Helper&&) = default;
-    Helper& operator=(Helper&&) = default;
+    Helper& operator=(Helper&&) = delete;
 
     /** @brief Constructor
      *