chore: make css side effects work

[pd4d10]

The CSS files shipped in the NPM package have a deep path, for example @blueprintjs/core/lib/css/blueprint.css. This PR changes *.css to **/*.css to make it work correctly

[palantirtech]

Thanks for your interest in palantir/blueprint, @pd4d10! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[adidahiya]

I'm surprised this has gone unnoticed for so long... your change looks correct but are you sure it wasn't working before?

[pd4d10]

This issue was found when bundled with rollup, see vitejs/vite#795 (Vite uses rollup under the hood).

It works correctly when bundled with webpack. Perhaps there are some specific strategy to process CSS, I guess.

[adidahiya]

Ok, good to know that this fix is specifically relevant to rollup.