[monitoringlib] Set ConnectionResetError as retryable

Author: the-glu

monitoring/monitorlib/fetch/__init__.py

@@ -719,6 +719,11 @@ def build_failing_query(t0) -> Query:
                 #   ('Connection aborted.', RemoteDisconnected('Remote end closed connection without response'))
                 # ...and this may be retryable
                 retryable = True
+            elif "ConnectionResetError" in str(e):
+                # This error manifests as:
+                #   ('Connection aborted.', ConnectionResetError(104, 'Connection reset by peer'))
+                # ...and this may be retryable
+                retryable = True
             else:
                 retryable = False
             failure_message = f"query_and_describe attempt {attempt + 1} from PID {os.getpid()} to {verb} {url} failed with {'' if retryable else 'non-'}retryable ConnectionError: {str(e)}\nAt {get_location()}"