Moving search bar from header to main in SearchResults

[Dex491]

Dependant on #190

• In the SearchResults page there will be no search bar in the header, and instead it is within the main
  • Conditional rendering to check- we pass a prop into the Header- searchBarVisible=true - we'll set it to false in the SearchResults component and not display it
  • This will be just for aesthetic purposes so there's not 2 search bars in SearchResults

[dogezen]

Might be better to pass a props to

specifying whether or not to show the search bar!

function Header({searchBarVisible=true})

Make it true by default