Fix task retry logic to respect retries for all exit codes

[amoghrajesh]

Why

Tasks that fail with non zero exit codes (like exit code 1) were not retrying even when retries were configured. This occurred when processes exited abnormally in a task, such as:

• External command failures (e.g., git fetch failing with exit code 1)
• Network timeouts in subprocess operations
• Any process that exits with a positive exit code before Python exception handling

Previously, only tasks terminated by signals (negative exit codes) would be retried. Normal failures with positive exit codes would immediately fail without checking if retries were available.

Testing

DAG used:

from airflow.sdk import DAG
from datetime import datetime
from airflow.providers.standard.operators.bash import BashOperator

dag = DAG(
    "test_retry_exit_code",
    start_date=datetime(2024, 1, 1),
    schedule=None,
    catchup=False,
)

task = BashOperator(
    task_id="git_fetch_fail",
    bash_command="git fetch invalid-remote || exit 1",
    retries=3,
    dag=dag,
)

Works as expected

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[amoghrajesh]

Forgot to cherry pick

[amoghrajesh]

Manual cherry pick: #58478