message: Add missing variant types for button component
diff: Custom button styles in numerous elements can be found here. Use any of the available button style types to quickly create a styled button.
  ## Variant
  -You can change the variant prop to give some predefined styles to the button component. For now, there are only 2 type of variants which are:
  +You can change the variant prop to give some predefined styles to the button component. For now, there are only 4 type of variants which are:
  - primary
  - secondary
  +- primary-outline
  +- secondary-outline
  +
  ```
  <Button variant='primary'>Primary</Button>
  <Button variant='secondary'>Secondary</Button>
  