Fix GhTokenInput not handling keyboard shortcut bug.

[sainthkh]

closes TryGhost/Ghost#11786

It was because ember-power-select was stopping the propagation of the events when ctrl/cmd or meta key is down.

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Explanation in more detail

GhTokenInput uses PowerSelect component of ember-power-select internally in app/components/gh-token-input/select-multiple.

When you open that component, you can find that it calls stopImmediatePropagation when ctrl/cmd or meta key is down.

  handleTriggerKeydown(e: KeyboardEvent) {
    if (this.args.onKeydown && this.args.onKeydown(this.storedAPI, e) === false) {
      e.stopImmediatePropagation();
      return;
    }
    if (e.ctrlKey || e.metaKey) {
      e.stopImmediatePropagation();
      return;
    }
    if ((e.keyCode >= 48 && e.keyCode <= 90) || isNumpadKeyEvent(e)) { // Keys 0-9, a-z or numpad keys
      (this.triggerTypingTask as unknown as Performable).perform(e);
    } else if (e.keyCode === 32) {  // Space
      this._handleKeySpace(this.storedAPI, e);
    } else {
      return this._routeKeydown(this.storedAPI, e);
    }
  }

Because of that, I had to dispatch event directly to the root of the Ghost admin app.

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• There's a clear use-case for this code change
• Commit message has a short title & references relevant issues
• The build will pass (run ember test from the repo root - will be core/client if working from the submodule in Ghost).

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[kevinansfield]

Thanks @sainthkh 🙌