Rollup merge of #121888 - cppcoffee:style, r=Nilstrieb

style library/core/src/error.rs

Add an extra blank line for clarity in distinguishing implementations.

library/core/src/error.rs

@@ -183,6 +183,7 @@ pub trait Error: Debug + Display {
     #[allow(unused_variables)]
     fn provide<'a>(&'a self, request: &mut Request<'a>) {}
 }
+
 mod private {
     // This is a hack to prevent `type_id` from being overridden by `Error`
     // implementations, since that can enable unsound downcasting.