Feat: Add possibility to hide previous / next button

[Chewbathra]

This pull request add possibility to hide previous / next button to force changing step programmatically.

I updated only PrimeNg library since i never used other ones.

[hakimio]

• You can already use custom template to achieve this
• You can't just add the feature to one single UI, you have to update all of them and make sure it looks good everywhere
• This seems to be a rather niche/rare feature request, so I am not sure if I want to introduce it. Please create a feature request where you explain why this is needed.