doc: fix -C flag usage
ref https://github.com/nodejs/node/commit/40eb3b79f1
❯ node -C development
Welcome to Node.js v18.13.0.
Type ".help" for more information.
>
❯ node -C=development
node: bad option: -C=development
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
ref https://github.com/nodejs/node/commit/40eb3b79f1
❯ node -C development
Welcome to Node.js v18.13.0.
Type ".help" for more information.
>
❯ node -C=development
node: bad option: -C=development