feat: Add append support for azdls

[Xuanwo]

Azdfs support append but we didn't implement it yet.

[gongyisheng]

I'd like to try on this issue when #2965 is done

[gongyisheng]

I'm going to work on this issue this weekend.

[gongyisheng]

Hi @Xuanwo, sorry I'm busy with my work recently, you can unassign me & give the opportunity for community. Sorry again.