Upgrades stylelint to 16

[JasonWeill]

Upgrades stylelint to version 16. Removes stylelint-config-prettier because, according to its README:

As of Stylelint v15 all style-related rules have been deprecated. If you are using v15 or higher and are not making use of these deprecated rules, this plugin is no longer necessary.

Amends jupyterlab#15948 per @krassowski.

[krassowski]

It looks like only some of the CI jobs were run? I do not see the lint job here. Maybe it is worth extracting to a separate PR and opening against the jupyterlab's main branch? If it passes we can merge it quickly.

[JasonWeill]

After extracting the package.json changes to a separate branch, independent of short-relative-date, and after rerunning jlpm install, I see an error in stylelint-csstree-validator:

$ npm run stylelint

> @jupyterlab/[email protected] stylelint
> jlpm stylelint:check --fix

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/Users/jweill/git/jupyterlab/node_modules/stylelint/lib/utils/isStandardSyntaxAtRule.js' imported from /Users/jweill/git/jupyterlab/node_modules/stylelint-csstree-validator/lib/index.js
    at new NodeError (node:internal/errors:406:5)
    at finalizeResolution (node:internal/modules/esm/resolve:233:11)
    at moduleResolve (node:internal/modules/esm/resolve:845:10)
    at defaultResolve (node:internal/modules/esm/resolve:1043:11)
    at ModuleLoader.defaultResolve (node:internal/modules/esm/loader:383:12)
    at ModuleLoader.resolve (node:internal/modules/esm/loader:352:25)
    at ModuleLoader.getModuleJob (node:internal/modules/esm/loader:228:38)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:85:39)
    at link (node:internal/modules/esm/module_job:84:36)

Notably, this package does not support Stylelint 16 (csstree/stylelint-validator#58) although there is a pull request to add support for it (csstree/stylelint-validator#59). I can open an issue about this.

[JasonWeill]

Closing this in favor of jupyterlab#16062, which is blocked.