Rename and clear bad code

src/dictionary_test.rs

@@ -35,7 +35,7 @@ pub enum DictionaryQuizMessage {
 }
 
 impl NavigatedPage<DictionaryQuizMessage> for DictionaryQuizState {
-    fn navigate(&self, message: &DictionaryQuizMessage) -> Option<Page> {
+    fn navigate(&mut self, message: &DictionaryQuizMessage) -> Option<Page> {
         match message {
             Back => Some(PreviousPage),
             _ => None,