v8: replace Buffer with FastBuffer in deserialize

Replace the Buffer constructor with a FastBuffer in v8.deserialize in
order to avoid calling the Buffer constructor and thus triggering a
deprecation warning from code inside the core.

Fixes: https://github.com/nodejs/node/issues/21181

PR-URL: https://github.com/nodejs/node/pull/21196
Fixes: https://github.com/nodejs/node/issues/21181


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>