Use SafePromiseResolve to replace the promise resolution steps

[mgaudet]

The goal here is to improve security of the web platform by avoiding execution of user code when WebIDL resolves a promise. This is done by using the SafePromiseResolve steps provided by the "Thenable Curtailment" proposal.

This PR only changes the promise resolve steps; Async iteration is left alone to keep compatible with TC39's async iteration steps.

• At least two implementers are interested (and none opposed):
  • Gecko
  • …
• Tests are written and can be reviewed and commented upon at:
  • …
• Implementation bugs are filed:
  • Chromium: …
  • Gecko: Bug 2077196 - Use SafePromiseResolve to resolve promises in WebIDL
  • WebKit: …
  • Deno: …
  • Node.js: …
  • webidl2.js: …
  • widlparser: …
• MDN issue is filed: …
• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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