List of multiple issues with pdf export

[lorenzo-rovigatti]

Hello!

Following #1581, I found the time to create a sort of Minimal Reproducible Examples for some issues I'm having with exporting a set of notes I'm writing to PDF.
I attach a folder containing a myst project that works well on a browser (using myst start), but suffers from several issues when converted to pdf (with myst build --pdf book.md).
This is a list of the issues I found:

1. Including figures in admonitions does not work (or works badly, depending on whether there are other images in the same file)
2. Using internal links to admonitions does not work
3. The markdown syntax [link text](sec:label) results in Section 1.1 (if the label refers to Section 1.1) rather than `link text' in the pdf. This applies also to bibliographic items, which is extremely annoying.
4. I didn't find a way to label latex equations defined using \begin{align}
5. Subfigures do not appear in the pdf.

Note that I'm using the most recent version (1.3.18).

myst_issues.zip