Add CSS module script/CSS modules

[Schweinepriester]

• https://github.com/WICG/webcomponents/blob/gh-pages/proposals/css-modules-v1-explainer.md
• Introduce CSS Module Script whatwg/html#4898
• https://groups.google.com/a/chromium.org/g/blink-dev/c/iT0bQjzD04k/m/VkHPoOFLBAAJ
• Chrome 93: https://www.chromestatus.com/feature/5948572598009856
• https://bugs.chromium.org/p/chromium/issues/detail?id=992499
• CSS Module Scripts mozilla/standards-positions#541
• https://lists.webkit.org/pipermail/webkit-dev/2021-June/031901.html

[atjn]

Related: #5928

[e111077]

I accidentally made a duplicate issue but here's more relevant info:

Stage 3: https://github.com/tc39/proposal-import-assertions
web.dev explainer: https://web.dev/css-module-scripts/

// styles.css
div {
  color: red;
}

// index.js
import styles from './styles.css' assert { type: "css" };
document.adoptedStyleSheets = [styles];
const success = getComputedStyle(document.querySelector('div')).color === 'rgb(255, 0, 0)'

// index.html
<script type="module" src="./index.js"></script>
<div>YOLO</div>

[o-t-w]

Chrome 123 added support for import attributes. Chrome already supported CSS module scripts but used a now deprecated syntax. Now that CSS module scripts work with the up-to-date syntax it seems like a good time to add this data to caniuse. All browsers have indicated that they will support this feature eventually.