Fatal error with Drupal 11.4 [#3607962]

Problem/Motivation

Hi, when updating to Drupal 11.4 I get:

Fatal error: Uncaught TypeError: Drupal\Core\Routing\StaticRouteDiscoveryBase::createRoute(): Argument #7 ($methods) must be of type array, string given, called in /var/www/html/web/core/lib/Drupal/Core/Routing/YamlRouteDiscovery.php on line 83 and defined in /var/www/html/web/core/lib/Drupal/Core/Routing/StaticRouteDiscoveryBase.php:77

This is because methods in the routing file are defines as strings, like 'GET', but should be arrays, like [GET].

Issue fork gutenberg_content_embed-3607962

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