build: add update-gyp script
build: add update-gyp script

Co-authored-by: Christian Clauss <585dd401264c1e46d17ebec1862e5d2a9b6a6c5d@me.com>
Reviewed-By: Jiawen Geng <8f5a7089e1809fdab8e8d97ec73a77a8b0770d74@gmail.com>
Reviewed-By: Christian Clauss <585dd401264c1e46d17ebec1862e5d2a9b6a6c5d@me.com>
PR-URL: https://github.com/nodejs/node-gyp/pull/2167

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