Random unittest faillure in test_file_is_draft_areas_limit_reached

core_filelib_testcase::test_file_is_draft_areas_limit_reached

Failed asserting that false is true.

/var/www/html/lib/tests/filelib_test.php:1728

/var/www/html/lib/phpunit/classes/advanced_testcase.php:80

diff --git a/lib/tests/filelib_test.php b/lib/tests/filelib_test.php

index b66a2481273..5306fc03e5d 100644

--- a/lib/tests/filelib_test.php

+++ b/lib/tests/filelib_test.php

@@ -1721,6 +1721,7 @@ EOF;

         $this->assertFalse(file_is_draft_areas_limit_reached($user->id));

         // Only one item was leaked from the bucket. So the bucket should become full again if we add a single item to it.

+        sleep(1);

         self::create_draft_file([

             'filename' => 'file2.png',

             'itemid' => $itemids[0],