chore: Removed extra whitespaces

Co-authored-by: Corentin ARNOULD <corentin.arn@gmail.com>

exercises/traits/README.md

@@ -1,6 +1,6 @@
 ### Traits
 
-A trait is a collection of methods. 
+A trait is a collection of methods.
 
 Data types can implement traits. To do so, the methods making up the trait are defined for the data type. For example, the `String` data type implements the `From<&str>` trait. This allows a user to write `String::from("hello")`.
 
@@ -8,7 +8,7 @@ In this way, traits are somewhat similar to Java interfaces and C++ abstract cla
 
 Some additional common Rust traits include:
 
-+ `Clone` (the `clone` method), 
++ `Clone` (the `clone` method),
 + `Display` (which allows formatted display via `{}`), and
 + `Debug` (which allows formatted display via `{:?}`).
 
@@ -17,4 +17,4 @@ Because traits indicate shared behavior between data types, they are useful when
 
 #### Book Sections
 
-- [Traits](https://doc.rust-lang.org/book/ch10-02-traits.html)
+- [Traits](https://doc.rust-lang.org/book/ch10-02-traits.html)