Sort notable traits in hover

Previously it was ordered by what accidentally happened to be the crate graph order, which isn't sensible, plus it caused changes when any change was done to salsa IDs.

crates/ide/src/hover.rs

@@ -505,6 +505,7 @@ fn notable_traits(
                 )
             })
         })
+        .sorted_by_cached_key(|(trait_, _)| trait_.name(db))
         .collect::<Vec<_>>()
 }