Merge pull request #1908 from z-song/analysis-zD4xrb

Apply fixes from StyleCI

src/Form/Field.php

@@ -402,7 +402,7 @@ public function rules($rules = null, $messages = [])
             $thisRuleArr = array_filter(explode('|', $this->rules));
 
             $this->rules = array_merge($thisRuleArr, explode('|', $this->rules));
-        } else if (is_string($rules)) {
+        } elseif (is_string($rules)) {
             $rules = array_filter(explode('|', "{$this->rules}|$rules"));
 
             $this->rules = implode('|', $rules);