Simplify deposit_event declaration in decl_module (#3506)

* simplify module deposit_event declaration

* fix

* bump version

* fix

* fix test

* fix doc

substrate/srml/scored-pool/src/lib.rs

@@ -228,7 +228,7 @@ decl_module! {
 		for enum Call
 		where origin: T::Origin
 	{
-		fn deposit_event<T, I>() = default;
+		fn deposit_event() = default;
 
 		/// Every `Period` blocks the `Members` set is refreshed from the
 		/// highest scoring members in the pool.