npx directus-extension build module error when style lang="sass"

[haidv1992]

Preflight Checklist

• I have completed all Troubleshooting Steps.
• I'm on the latest version of Directus.
• There's no other issue that already describes my problem.

Describe the Bug

haidv@haidvs-iMac dashboard % npx directus-extension build
⠋ Building Directus extension...(node:54486) UnhandledPromiseRejectionWarning: Error: Cannot find module 'sass'
Require stack:
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/@vue/compiler-sfc/dist/compiler-sfc.cjs.js
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/rollup-plugin-vue/dist/sfc.js
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/rollup-plugin-vue/dist/index.js
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/@directus/extensions-sdk/dist/cjs/cli/commands/build.js
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/@directus/extensions-sdk/dist/cjs/cli/run.js
- /usr/local/var/www/directus/directus-project/src/dashboard/node_modules/@directus/extensions-sdk/cli.js

Screen.Recording.2021-09-08.at.09.09.37.1.mov

To Reproduce

create module extension
style with lang="scss"
npx directus-extension build

What version of Directus are you using?

v9.0.0-rc.92

What version of Node.js are you using?

v14.17.1

What database are you using?

Mysql

What browser are you using?

chorme

What operating system are you using?

macOS

How are you deploying Directus?

locally