Add the slice print statement

Since this is shown in the text and does not add too much complexity. I was
following along without Rust Playground and not havinf this piece of code forced
me to open a new page (more friction).

Author: edilmedeiros

08_traits_and_reading_bytes.md

@@ -46,6 +46,7 @@ fn main() {
     let version = u32::from_le_bytes(buffer);
 
     println!("Version: {}", version);
+    println!("Bytes slice: {:?}", bytes_slice);
 }
 ```