Fix typo.

core/http/client.py

@@ -190,7 +190,7 @@ async def fetch(
         except OSError as e:
             metrics["httpclient_timeouts"] += 1
             return ERR_TIMEOUT, {}, b"Connection error: %s" % smart_bytes(e)
-        except (asyncio.TimeoutError, TimeoutError):
+        except asyncio.TimeoutError:
             metrics["httpclient_timeouts"] += 1
             return ERR_TIMEOUT, {}, b"Connection timed out"
         # Proxy CONNECT