[ErrorHandler] Fixed tests

Author: lyrixx

Tests/Exception/FlattenExceptionTest.php

@@ -209,6 +209,7 @@ public function testToArray(\Throwable $exception, string $expectedClass)
                     'namespace' => '', 'short_class' => '', 'class' => '', 'type' => '', 'function' => '', 'file' => 'foo.php', 'line' => 123,
                     'args' => [],
                 ]],
+                'properties' => [],
             ],
         ], $flattened->toArray());
     }