fix: asyncio methods should use asyncio.sleep()

not time.sleep()

Author: Shlomi Kushchi

alpaca_trade_api/polygon/streamconn.py

@@ -133,7 +133,7 @@ async def _ensure_ws(self):
                                       f'Polygon Connection Failed ({e})'})
                 self._ws = None
                 self._retries += 1
-                time.sleep(self._retry_wait * self._retry)
+                await asyncio.sleep(self._retry_wait * self._retry)
         else:
             raise ConnectionError("Max Retries Exceeded")