fix(quiz2): fix comment regarding hints
Change the comment on quiz2.rs, since there are no hints.
// - The input is going to be a Vector of a 2-length tuple,
// the first element is the string, the second one is the command.
// - The output element is going to be a Vector of strings.
-// Execute `rustlings hint quiz2` or use the `hint` watch subcommand for a hint.
+// No hints this time!
// I AM NOT DONE
