Improve a bit the word selection algorithm

src/services/words.rs

@@ -14,7 +14,7 @@ pub fn get_word_of_the_day() -> String {
     let year = date.year() as usize;
     let month = date.month() as usize;
     let day = date.day() as usize;
-    let index = year + month + day;
+    let index = year + month * day;
 
     WORDS[index % WORDS.len()].clone()
 }