fix: cancel function invocation when deadline exceeded

- for now, this will mainly work in cases when the task is still
  in the queue
- once the task is running & making the function call, there is no
  mechanism to tell the call to cancel

JIRA: CQ-1005

Author: lupko

gooddata-flexconnect/gooddata_flexconnect/function/flight_methods.py

@@ -150,6 +150,11 @@ def get_flight_info(
                 # XXX: this should be enhanced to implement polling
                 task_result = self._ctx.task_executor.wait_for_result(task.task_id, self._call_deadline)
             except TaskWaitTimeoutError:
+                cancelled = self._ctx.task_executor.cancel(task.task_id)
+                _LOGGER.warning(
+                    "flexconnect_fun_call_timeout", task_id=task.task_id, fun=task.fun_name, cancelled=cancelled
+                )
+
                 raise ErrorInfo.for_reason(
                     ErrorCode.TIMEOUT, f"GetFlightInfo timed out while waiting for task {task.task_id}."
                 ).to_timeout_error()