Use equals not identical operator when comparing the request index to the recording index.

Author: bwood

src/VCR/Cassette.php

@@ -30,7 +30,7 @@ public function playback(Request $request, int $index = 0): ?Response
  {
  foreach ($this->storage as $recording) {
  $storedRequest = Request::fromArray($recording['request']);
- if ($index === $recording['index']) {
+ if ($index == $recording['index']) {
  if ($storedRequest->matches($request, $this->getRequestMatchers())) {
  return Response::fromArray($recording['response']);
  }