Fix figure caption show rule

[Andrew15-5]

As was noticed in https://forum.typst.app/t/how-to-avoid-numbering-subfigure-captions-when-using-legal-numbering/6149, par show rule applies to figure captions (in super). Which is not the case when subpar is not used. After a quick figure caption show rule search the issue is obvious: the block wrapper is missing. Adding it, fixes the problem.

Do I need to add a test for this? I guess also par-based show rule. Or like #show par: set text(green).

You can also do

#{
          show figure.caption: it => {
            show: block
            num
            [ ]
            it.body
          }
}

But I guess it's an advanced and confusing version.

[Andrew15-5]

It fails without fix. I also made it compile-only. Also, you don't have .gitignore for out directory, so the repository has a bunch of those, even though they don't serve any tt run purpose.

[tingerrr]

I would prefer an ephemeral test, but this will do just fine. Thanks!

Regarding the .gitignore, that's probably an issue in how currently sets up tests, I'm working on fixing this in Tytanic itself. But adding the correct .gitignore would be great anyway.

[Andrew15-5]

Actually, the ignore issue is not that bad: #41.