message: feat(leadspace): add gradient knob to story
  ### Related Ticket(s)
  Closes
  ### Description
  Adds a storybook knob to control the `gradient-style-scheme` attribute values of `'with-gradient'` and `''`
  ### Changelog
  **Changed**
  Added knob to leadspace stories
diff: @@ -30,6 +30,11 @@ const navigationOptions = [
  'none',
  ];
  +const gradientOptions = {
  + 'With Gradient': 'with-gradient',
  + 'No Gradient': '',
  +};
  +
  const navigationWithTagGroup = html`
  <dds-tag-group slot="navigation">
  <dds-tag-link href="https://example.com">Marketing Analytics</dds-tag-link>
  @@ -707,6 +712,11 @@ export default {
  label: getAriaLabel(icon),
  };
  }),
  + gradientStyleScheme: select(
  + 'Gradient (gradient-style-scheme)',
  + gradientOptions,
  + 'with-gradient'
  + ),
  alt: text('Image alt text (alt):', 'Image alt text'),
  defaultSrc: text('Default image (defaultSrc):', leadspaceImg),
  }),
  