Merge pull request #1293 from tysonliddell/fix_self_parameter

fix: Remove superfluous &self indirection

exercises/enums/enums2.rs

@@ -10,7 +10,7 @@ enum Message {
 
 impl Message {
     fn call(&self) {
-        println!("{:?}", &self);
+        println!("{:?}", self);
     }
 }