chore(clippy): #[must_use]

Co-authored-by: Pierre Tondereau <ptondereau@users.noreply.github.com>

Author: kakserpom

src/types/array/mod.rs

@@ -688,6 +688,7 @@ impl ZendHashTable {
     /// // Works with numeric keys too
     /// ht.entry(42i64).or_insert("value at index 42");
     /// ```
+    #[must_use]
     pub fn entry<'a, 'k, K>(&'a mut self, key: K) -> Entry<'a, 'k>
     where
         K: Into<ArrayKey<'k>>,