message: Fix wrong API method name in README
diff: @@ -183,7 +183,7 @@ embla.scrollNext()
  embla.scrollTo(2)
  embla.changeOptions({ loop: true })
  embla.on('select', () => {
  - console.log(`Selected scroll is now ${embla.selectedScroll()}!`)
  + console.log(`Selected snap index is ${embla.selectedScrollSnap()}!`)
  })
  ```
  