Fix <Language showName /> prop type (#5265)
Fix <Language showName /> prop type (#5265)

There isn‘t a `boolean` prop type, so this was throwing an error when Netlify built the site.
existentialism/prettier,prettier/prettier,prettier/prettier,rattrayalex/prettier,rattrayalex/prettier,existentialism/prettier,existentialism/prettier,rattrayalex/prettier,jlongster/prettier,existentialism/prettier,prettier/prettier,prettier/prettier