InputGroupAddon: Button in addon padding

[brecht-vermeersch]

  <InputGroup>
    <InputGroupAddon>
      <Button severity="secondary">btn</Button>
    </InputGroupAddon>
    <InputText />
  </InputGroup>

results in

This can also be seen on the documentation page: https://primevue.org/inputgroup/#button vs https://tailwind.primevue.org/inputgroup/#button