asynchronously close of response (#309)

The response is closed synchronously in the async path, unnecessarily
blocking.
The PR closes the response asynchronously instead

Author: alex-does-stuff

replicate/client.py

@@ -305,7 +305,7 @@ async def handle_async_request(self, request: httpx.Request) -> httpx.Response:
             ):
                 return response
 
-            response.close()
+            await response.aclose()
 
             sleep_for = self._calculate_sleep(attempts_made, response.headers)
             await asyncio.sleep(sleep_for)