function buildStyle(_, options) {
  return htmlSafe(
    keys(options).reduce((style, key) => `${style}${key}:${options[key]};`, ''),
  );
}
Helper to build a style from its options. Also returns
a `SafeString` which avoids the style warning. Make sure
you don't pass user input to this helper.

@method buildStyle
@param {Array} _ not used
@param {Object} options The options that become styles
@return {String} The style sting.