cleanup <weight></weight> from docs comments (#13350)

* cleanup <weight></weight> from docs comments

* Changes to address review commnets

* Fix CI cargo test --docs

---------

Co-authored-by: parity-processbot <>

substrate/frame/timestamp/src/lib.rs

@@ -171,10 +171,8 @@ pub mod pallet {
 			T::WeightInfo::on_finalize()
 		}
 
-		/// # <weight>
+		/// ## Complexity
 		/// - `O(1)`
-		/// - 1 storage deletion (codec `O(1)`).
-		/// # </weight>
 		fn on_finalize(_n: BlockNumberFor<T>) {
 			assert!(DidUpdate::<T>::take(), "Timestamp must be updated once in the block");
 		}
@@ -192,12 +190,11 @@ pub mod pallet {
 		///
 		/// The dispatch origin for this call must be `Inherent`.
 		///
-		/// # <weight>
+		/// ## Complexity
 		/// - `O(1)` (Note that implementations of `OnTimestampSet` must also be `O(1)`)
 		/// - 1 storage read and 1 storage mutation (codec `O(1)`). (because of `DidUpdate::take` in
 		///   `on_finalize`)
 		/// - 1 event handler `on_timestamp_set`. Must be `O(1)`.
-		/// # </weight>
 		#[pallet::call_index(0)]
 		#[pallet::weight((
 			T::WeightInfo::set(),