add loading prop to drawer

[wc-matteo]

This function solves the problem (这个功能解决的问题)

makes it easier to put an "async" component inside a drawer

Expected API (期望的 API)

loading prop like other elements

[07akioni]

Loading prop? What does it looks like.

[wc-matteo]

like a button's loading prop. Makes a spinner appear inside the drawer. I guess n-spin could be used for the purpose but a prop is handier...

[Talljack]

What's the usage scenario of this? I don’t think other frameworks have this feature

[jahnli]

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