fix: add default value for hasShow in Show.tsx

[FredericEspiau]

Prevents having hasShow on a div element, because React complains about this

Warning: React does not recognize the `hasShow` prop on a DOM element. If you intentionally want it to appear in the DOM as a custom attribute, spell it as lowercase `hasshow` instead. If you accidentally passed it from a parent component, remove it from the DOM element.
    in div (created by ShowView)
    in ShowView (created by Show)

[djhi]

Thanks!