[cupertino_http] StreamedResponse does not close after cancelling the response stream

[Colton127]

In cupertino_http, cancelling the stream on a StreamedResponse does not close the underlying connection.

final client = CupertinoClient.fromSessionConfiguration(URLSessionConfiguration.ephemeralSessionConfiguration());
final request = Request('GET', Uri.parse('https://cachefly.cachefly.net/100mb.test'));
final streamedResponse = await client.send(request);
final streamSubscription = streamedResponse.stream.listen(null);
await Future.delayed(const Duration(seconds: 5));
await streamSubscription.cancel();

After cancelling the stream subscription, the connection remains open until the full body is received:

In contrast, the standard IOClient closes the connection when the stream subscription is cancelled. Notice the "Timespan":

I opened the same issue for cronet_http here.