Add error handling for illegal request methods (MethodNotAllowedException)

[samtuke]

Currently if an illegal request method is used for communication with the API, no response is returned and a PHP Fatal Error is triggered (Uncaught Symfony\Component\Routing\Exception\MethodNotAllowedException in /base-distribution/var/cache/prod/phplist4coreProdProjectContainerUrlMatcher.php:58).

Add exception handling and error reporting for such cases.