os: move tmpDir() to EOL

The tmpDir alias was deprecated in 7.0.0

PR-URL: https://github.com/nodejs/node/pull/31169


Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>