chore: Alter whitespace for consistency

* Add newline after "I AM DONE" in exercises for consistency
* Remove trailing whitespace from exercises

exercises/generics/generics1.rs

@@ -1,4 +1,4 @@
-// This shopping list program isn't compiling! 
+// This shopping list program isn't compiling!
 // Use your knowledge of generics to fix it.
 
 // I AM NOT DONE

exercises/generics/generics2.rs

@@ -2,6 +2,7 @@
 // Rewrite it using generics so that it supports wrapping ANY type.
 
 // I AM NOT DONE
+
 struct Wrapper {
     value: u32
 }
@@ -18,11 +19,11 @@ mod tests {
 
     #[test]
     fn store_u32_in_wrapper() {
-        assert_eq!(Wrapper::new(42).value,  42);
+        assert_eq!(Wrapper::new(42).value, 42);
     }
 
     #[test]
     fn store_str_in_wrapper() {
         assert_eq!(Wrapper::new("Foo").value, "Foo");
     }
-}
+}

exercises/generics/generics3.rs

@@ -1,13 +1,14 @@
 // An imaginary magical school has a new report card generation system written in Rust!
-// Currently the system only supports creating report cards where the student's grade 
-// is represented numerically (e.g. 1.0 -> 5.5). 
-// However, the school also issues alphabetical grades (A+ -> F-) and needs 
+// Currently the system only supports creating report cards where the student's grade
+// is represented numerically (e.g. 1.0 -> 5.5).
+// However, the school also issues alphabetical grades (A+ -> F-) and needs
 // to be able to print both types of report card!
 
-// Make the necessary code changes to support alphabetical report cards, thereby making 
+// Make the necessary code changes to support alphabetical report cards, thereby making
 // the second test pass.
 
 // I AM NOT DONE
+
 pub struct ReportCard {
     pub grade: f32,
     pub student_name: String,
@@ -16,7 +17,7 @@ pub struct ReportCard {
 
 impl ReportCard {
     pub fn print(&self) -> String {
-        format!("{} ({}) - achieved a grade of {}", 
+        format!("{} ({}) - achieved a grade of {}",
             &self.student_name, &self.student_age, &self.grade)
     }
 }
@@ -28,8 +29,8 @@ mod tests {
     #[test]
     fn generate_numeric_report_card() {
         let report_card = ReportCard {
-            grade: 2.1, 
-            student_name: "Tom Wriggle".to_string(), 
+            grade: 2.1,
+            student_name: "Tom Wriggle".to_string(),
             student_age: 12,
         };
         assert_eq!(report_card.print(), "Tom Wriggle (12) - achieved a grade of 2.1");
@@ -39,10 +40,10 @@ mod tests {
     fn generate_alphabetic_report_card() {
         // TODO: Make sure to change the grade here after you finish the exercise.
         let report_card = ReportCard {
-            grade: 2.1, 
-            student_name: "Gary Plotter".to_string(), 
+            grade: 2.1,
+            student_name: "Gary Plotter".to_string(),
             student_age: 11,
         };
         assert_eq!(report_card.print(), "Gary Plotter (11) - achieved a grade of A+");
     }
-}
+}