Restore (and fix) ownership example

Author: romain-at-adacore

courses/rust_essentials/130_memory_management/03_ownership.rst

@@ -39,9 +39,9 @@ Ownership Principles
   {
       let poodle = String::from("ball"); // 'poodle' owns the ball
       let yorkie = poodle; // 'poodle' lets go, 'yorkie' picked it up
-            
+
+      // println!("{}", poodle); // Error
       println!("{}", yorkie);
-      println!("{}", poodle);
   } // 'yorkie' drops the ball, and leaves
   // 'poodle' leaves quietly