thumbnail_urlString property in SharedElement interface is incorrectly named

[notajingoist]

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• Summary The thumbnail_urlString property currently defined in the SharedElement interface should be thumbnail_url (see https://www.figma.com/developers/api#library-items-types).

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. StackOverflow, personal fork, etc.)

  interface SharedElement extends ComponentMetadata {
  ...
  readonly thumbnail_urlString: string;
  ...
  }

  should instead be

  interface SharedElement extends ComponentMetadata {
  ...
  readonly thumbnail_url: string;
  ...
  }