[ticket/15987] Go back to previous table definition type

This will still allow using the 'tables' parameter array but will also ensure
full backward compatibility and compatibility with extensions that will add
more tables to the 'tables' array.

PHPBB3-15987

phpBB/phpbb/di/container_builder.php

@@ -160,7 +160,6 @@ class container_builder
 			{
 				$this->container_extensions = [
 					new extension\core($this->get_config_path()),
-					new extension\tables(),
 				];
 
 				if ($this->use_extensions)
@@ -168,6 +167,9 @@ class container_builder
 					$this->load_extensions();
 				}
 
+				// Add tables extension after all extensions
+				$this->container_extensions[] = new extension\tables();
+
 				// Inject the config
 				if ($this->config_php_file)
 				{