Using `path.join(os.tmpdir(), 'file')` on a multi-user system can lead
to file collisions where the file already exists but is owned by a
different user and cannot be removed or overwritten. Other tests in
`parallel/test-watch-mode-files_watcher` use `common/tmpdir` instead
so switch to that for consistency.
PR-URL: https://github.com/nodejs/node/pull/45211
Refs: https://github.com/nodejs/node/pull/44366
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
