fix: clarify misleading 'Error' comment in print_display example (#1870)

Author: Abhinav-ranish

src/hello/print/print_display.md

@@ -94,8 +94,9 @@ fn main() {
     println!("Display: {}", point);
     println!("Debug: {:?}", point);
 
-    // Error. Both `Debug` and `Display` were implemented, but `{:b}`
-    // requires `fmt::Binary` to be implemented. This will not work.
+    // The following line would not compile: both `Debug` and `Display`
+    // were implemented, but `{:b}` requires `fmt::Binary` to be
+    // implemented, which it hasn't been for `Point2D`.
     // println!("What does Point2D look like in binary: {:b}?", point);
 }
 ```