Unsubscribe SemanticFormsUniqueValue, as it will be deleted

Change-Id: I9eb70f384ee41e900d8a3de9aada687e5710a838
(cherry picked from commit 226544b53969daa4c0349f8ae5fb415539241b0e)
Merge "Unsubscribe SemanticFormsUniqueValue, as it will be deleted" into REL1_23