diff --git a/core/tests/Drupal/Tests/Composer/Plugin/Scaffold/fixtures/composer-plugin-implements-scaffold-events/src/ComposerPluginImplementsScaffoldEvents.php b/core/tests/Drupal/Tests/Composer/Plugin/Scaffold/fixtures/composer-plugin-implements-scaffold-events/src/ComposerPluginImplementsScaffoldEvents.php
index 63b785fcf1b3d9fd96dc29b02c0edec900da4ac3..309b2d0dca6a9b59eca6d18ecc4a5cd9b6dbb39f 100644
--- a/core/tests/Drupal/Tests/Composer/Plugin/Scaffold/fixtures/composer-plugin-implements-scaffold-events/src/ComposerPluginImplementsScaffoldEvents.php
+++ b/core/tests/Drupal/Tests/Composer/Plugin/Scaffold/fixtures/composer-plugin-implements-scaffold-events/src/ComposerPluginImplementsScaffoldEvents.php
@@ -43,21 +43,21 @@ public static function postDrupalScaffoldCmd(Event $event): void {
   /**
    * {@inheritdoc}
    */
-  public function activate(Composer $composer, IOInterface $io) {
+  public function activate(Composer $composer, IOInterface $io): void {
 
   }
 
   /**
    * {@inheritdoc}
    */
-  public function deactivate(Composer $composer, IOInterface $io) {
+  public function deactivate(Composer $composer, IOInterface $io): void {
 
   }
 
   /**
    * {@inheritdoc}
    */
-  public function uninstall(Composer $composer, IOInterface $io) {
+  public function uninstall(Composer $composer, IOInterface $io): void {
 
   }