[Bug]: sporadical failure of the test_api_ts_forecasting_example integration test

[Lopa10ko]

Current Behavior

The integration test fails quite often, passing NaN-containing inputs between nodes.

Troubled pipelines

• [x] #1300
• [x] #1302
• [ ] ...

Steps to reproduce

In examples/simple/time_series_forecasting/api_forecasting.py::run_ts_forecasting_example pass initial_assumption to a Fedot instance like so:

def run_ts_forecasting_example(dataset='australia', horizon: int = 30, timeout: float = None,
                               visualization=False, validation_blocks=2, with_tuning=True):
    train_data, test_data, label = get_ts_data(dataset, horizon, validation_blocks=validation_blocks)
    # init model for the time series forecasting

    model = Fedot(problem='ts_forecasting',
                  task_params=Task(TaskTypesEnum.ts_forecasting,
                                   TsForecastingParams(forecast_length=horizon)).task_params,
                  timeout=timeout,
                  n_jobs=-1,
                  metric='mae',
                  with_tuning=with_tuning,
                  initial_assumption=Pipeline().load('<path_to_troubled_pipeline_dir>'))
   ...

Context

possibly related to issues with ETSModel #1285

[Lopa10ko]

[!NOTE]
One is welcomed to provide new troubled pipelines for this issue (If managed to save Pipeline obj before facing some kind of error).