deps: V8: update postmortem metadata generation script

Update postmortem metadata constants for V8 7.7 in Node.js.

PR-URL: https://github.com/nodejs/node/pull/28918


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>