Add fail_on_file_not_exist to SFTPToGCSOperator

[nguy4130]

Fixes: #41472

Adding fail_on_file_not_exist param to SFTPToGCSOperator so that user can configure the parameter and operator will not fail in case of sftp file not exist.

Note that this is only added to the non-wildcard source file path as that code already kind of handles when the file does not exist.

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Tested with a local DAG

from airflow import DAG
from airflow.providers.google.cloud.transfers.sftp_to_gcs import SFTPToGCSOperator
from datetime import datetime, timedelta

default_args = {
    "owner": "airflow",
    "retries": 1,
    "retry_delay": timedelta(minutes=1),
}

with DAG(
    dag_id="sftp_to_gcs_example",
    default_args=default_args,
    description="Transfer a file from SFTP to GCS",
    start_date=datetime(2023, 1, 1),
    catchup=False,
    tags=["example", "sftp", "gcs"],
) as dag:
    transfer_file = SFTPToGCSOperator(
        task_id="transfer_file",
        source_path="test.mv.dba",
        sftp_conn_id="sftp_default",
        gcp_conn_id="google_cloud_default",
        destination_bucket="airflow",
        destination_path="test/test.mv.db",
        fail_on_file_not_exist=False,
    )

when fail_on_file_not_exist=False, the DAG exited gracefully

when fail_on_file_not_exist=True or not set, the DAG failed with error (existing behavior)

[potiuk]

Nice - but CI does not agree :)

[potiuk]

Still :(

[nguy4130]

@potiuk CI should be happy now!

[potiuk]

@potiuk CI should be happy now!

🤞