test: use Object for tests variable in fs trace test

PR-URL: #43585
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>

test/parallel/test-trace-events-fs-sync.js

@@ -6,7 +6,7 @@ const fs = require('fs');
 const path = require('path');
 const util = require('util');
 
-const tests = new Array();
+const tests = Object.create(null);
 
 let gid = 1;
 let uid = 1;