feat: implement clone for IntoPipeSystem (#20108)

# Objective

Implement `Clone` for `IntoPipeSystem`, allowing for `T: IntoSystem +
Clone` patterns.


## Precedence

Same clone implementation/docs as `CombinatorSystem`

crates/bevy_ecs/src/system/combinator.rs

@@ -252,6 +252,7 @@ where
 }
 
 /// An [`IntoSystem`] creating an instance of [`PipeSystem`].
+#[derive(Clone)]
 pub struct IntoPipeSystem<A, B> {
     a: A,
     b: B,