Remove API CRUD methods typehint

API may not always return an object or array but only integers or
strings for example.

If CRUD methods force return type, it may throw TypeError exception.

src/Api.php

@@ -114,9 +114,9 @@ protected function findOne(string $endpoint, $id, array $filters = [])
      * @param int    $id
      * @param        $attributes
      *
-     * @return array
+     * @return mixed|array
      */
-    protected function update(string $endpoint, $id, $attributes): array
+    protected function update(string $endpoint, $id, $attributes)
     {
         $key = $endpoint.'/'.$id.'?';
 
@@ -129,9 +129,9 @@ protected function update(string $endpoint, $id, $attributes): array
      * @param string $endpoint
      * @param        $attributes
      *
-     * @return array
+     * @return mixed|array
      */
-    protected function create(string $endpoint, $attributes): array
+    protected function create(string $endpoint, $attributes)
     {
         return $this->getTransport()->request('/'.$endpoint, $attributes, 'post') ?? [];
     }
@@ -142,9 +142,9 @@ protected function create(string $endpoint, $attributes): array
      * @param string $endpoint
      * @param int    $id
      *
-     * @return array
+     * @return mixed|array
      */
-    protected function delete(string $endpoint, $id): array
+    protected function delete(string $endpoint, $id)
     {
         $key = $endpoint.'/'.$id.'?';
         $this->deleteCache($key);