doc: make explicit reverting node_version.h changes

Add an explicit command to revert changes to `node_version.h` when
cherry-picking the release commit to the `master` branch.

PR-URL: https://github.com/nodejs/node/pull/36461
Refs: https://github.com/nodejs/node/pull/36460
Refs: https://github.com/nodejs/node/pull/36385


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Danielle Adams <adamzdanielle@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Shelley Vohr <codebytere@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>