Update isMethodType to compare case-insensitively

This commit updates the isMethodType function in the HTTP Request class to compare the HTTP method type case-insensitively. This change is necessary to allow for more flexible matching of HTTP method types.

Closes #3335308

core/lib/Drupal/Core/Form/FormState.php

@@ -642,7 +642,7 @@ public function setMethod($method) {
    * {@inheritdoc}
    */
   public function isMethodType($method_type) {
-    return $this->method === strtoupper($method_type);
+    return strtoupper($this->method) === strtoupper($method_type);
   }
 
   /**