Reduce legacy event log level to debug

This is to reduce log flooding on info log level, which is currently expected tue to deprecated event use in many apps and core: #18331
This information is helpful for developers only, hence should be sufficient as debug log. Especially due to the extremely high frequency this log can happen, this currently practically forces admins to disable info logs, which conflicts with other needs.

Signed-off-by: MichaIng <micha@dietpi.com>

Author: MichaIng

lib/private/EventDispatcher/SymfonyAdapter.php

@@ -63,7 +63,7 @@ public function dispatch($eventName, $event = null) {
 			$this->eventDispatcher->dispatch($eventName, $event);
 		} else {
 			// Legacy event
-			$this->logger->info(
+			$this->logger->debug(
 				'Deprecated event type for {name}: {class}',
 				[ 'name' => $eventName, 'class' => is_object($event) ? get_class($event) : 'null' ]
 			);