Uniques: Small fix in docs (#12143)

* small fix in docs

* Update frame/uniques/src/lib.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

* Update lib.rs

* Update lib.rs

* Update lib.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/frame/uniques/src/lib.rs

@@ -910,7 +910,8 @@ pub mod pallet {
 
 		/// Approve an item to be transferred by a delegated third-party account.
 		///
-		/// Origin must be Signed and must be the owner of the `item`.
+		/// The origin must conform to `ForceOrigin` or must be `Signed` and the sender must be
+		/// either the owner of the `item` or the admin of the collection.
 		///
 		/// - `collection`: The collection of the item to be approved for delegated transfer.
 		/// - `item`: The item of the item to be approved for delegated transfer.