resolveIconForId(iconId) {
    const splitIconId = iconId.split(':');
    if (splitIconId.length !== 3) {
      throw new Error(`Incorrect iconId: ${iconId}. Format: <namespace>:<iconset>:<icon>`);
    }

    return this.resolveIcon(splitIconId[0], splitIconId[1], splitIconId[2]);
  }
Resolves icon for the given icon id. Returns the icon as a svg string.

@param {string} iconId
@returns {Promise<TemplateResult>}