Mention component document cannot get in v16.2.x

[iscdev01]

Reproduction link

https://stackblitz.com/edit/ng-zorro-antd-ivy?file=src%2Fapp%2Fapp.component.ts

Steps to reproduce

Go directly to the official documentation：https://ng.ant.design/version/16.2.x/components/collapse/en

What is expected?

successfully obtained

What is actually happening?

1.Screen display is blank 2.Browser console error：TypeError: Cannot read properties of undefined (reading 'getMentions')

Environment	Info
ng-zorro-antd	16.2.2
Browser	chrome

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Ignore the provided reproduction link.

[ParsaArvanehPA]

Hi, I hope this message finds you well. This was actually a known bug fixed in PR #8146.

What it the policy of ng-zorro when it comes to maintaining older versions? Should this pr be cherrypicked? WDYT? @HyperLife1119 @OriginRing