accordion组件中的index.less存在无效less函数，导致构建失败

[CrystalGrape]

Version

4.0.0

Environment

Angular CLI: 12.2.9 Node: 12.18.4

Reproduction link

https://stackblitz.com/edit/ng-zorro-antd-mobile-start?file=src/app/app.component.ts

Steps to reproduce

ng build -c production构建工程，出现错误：
✔ Browser application bundle generation complete.
✔ Copying assets complete.
✖ Index html generation failed.
undefined:1:13358: property missing ':'
将ng-zorro-antd-mobile/components/accordion/style/index.less第36行.encoded-svg-background('right');注释后发现正常构建

What is expected?

构建成功

What is actually happening?

ng build -c production
✔ Browser application bundle generation complete.
✔ Copying assets complete.
✖ Index html generation failed.
undefined:1:13358: property missing ':'

Other?

实际使用版本是5.0.0，此处无法选择
仅在构建时报错！