Invoke margin links inside sphinx-proof blocks

[ShashShukla]

I would like to add a link in the margin of a jupyter-book, referring to text inside a sphinx-proof block, from within the sphinx-proof block. A generic example:

````{prf:example} 
Text.
```{margin} Relevant reference
[link](/URL)
```
```{figure} /figure-path
:name: fig
Caption.
```
````

While the text and image render inside the example block as desired, the margin link is rendered in the margin of the sphinx-proof block instead of in the "global" book margin. A way to thus render the margin link in the "global" margin instead would be very helpful.

Version information:

• sphinx: 4.3.0
• sphinx-proof: 0.1.3
• jupyter-sphinx: 0.3.2
• sphinx-book-theme: 0.1.1
• jupyter-book: 0.12.0

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