Add missing mdn_url keys for CSS static methods, Symbol dispose, and Viewport segments

[pepelsbey]

Summary

Add missing mdn_url keys for:

• CSS static methods
  • https://developer.mozilla.org/docs/Web/API/CSS/factory_functions_static
• Symbol dispose
  • https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/AsyncDisposableStack/Symbol.asyncDispose
  • https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/AsyncIterator/Symbol.asyncDispose
  • https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/DisposableStack/Symbol.dispose
  • https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Iterator/Symbol.dispose
• Viewport segments
  • https://developer.mozilla.org/docs/Web/API/Viewport/segments

[github-actions]

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