test: remove unneeded --expose-internals

test/wpt/test-timers.js does not appear to need the `--expose-internals`
flag. Remove it.

PR-URL: nodejs#27608
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Yongsheng Zhang <zyszys98@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

test/wpt/test-timers.js

@@ -1,7 +1,5 @@
 'use strict';
 
-// Flags: --expose-internals
-
 require('../common');
 const { WPTRunner } = require('../common/wpt');