fix: always create GitHook even when repo_url is provided

[nailo2c]

Closes: #52332

Why

A corner case in GitDagBundle causes pulling DAGs from a private GitHub repository to fail whenever repo_url is set in dag_bundle_config_list.

How

Move the try / except block before the repo_url detection so that the GitHook is always created.

What

I tested with a private repo and created an example DAG:

from datetime import datetime, timedelta

from airflow import DAG
from airflow.operators.bash import BashOperator

default_args = {
    "owner": "airflow",
    "depends_on_past": False,
    "retries": 1,
    "retry_delay": timedelta(minutes=5),
}

with DAG(
    dag_id="hello_airflow",
    default_args=default_args,
    description="A simple hello-world DAG",
    schedule="0 0 * * *",
    start_date=datetime(2025, 7, 4),
    catchup=False,
    tags=["example"],
) as dag:

    say_hello = BashOperator(
        task_id="say_hello",
        bash_command='echo "Hello Airflow!"',
    )

Bundle configuration

dag_bundle_config_list = [{"name": "dags-folder", "classpath": "airflow.providers.git.bundles.git.GitDagBundle", "kwargs": {"repo_url": "git@github.com:nailo2c/my_repo.git" , "tracking_ref": "main", "subdir": "dags"}}]

Git connection

airflow connections add git_default \
  --conn-json '{
    "conn_type": "git",
    "login": "git",
    "host": "github.com",
    "extra": {
      "private_key": "*****",
      "strict_host_key_checking": "no"
    }
  }'

It works well

[potiuk]

Can you please add tests for it ? It seems super-suspicious to see tests passing both before and after the change - which basically means that it's not tested.

[nailo2c]

You're right, I should add a test for it, even though it's a small logic change. I'll be more mindful about this in future contributions. Thanks for the reminder! Let me add a test for it :)

[nailo2c]

Done, this test fails on the main branch but passes with this PR. The test supplies a repo_url when constructing GitDagBundle. On main branch, the presence of repo_url prevents GitHook from being instantiated, reproducing the original bug.

[potiuk]

You're right, I should add a test for it, even though it's a small logic change. I'll be more mindful about this in future contributions. Thanks for the reminder! Let me add a test for it :)

Thanks - yeah. No matter how small logic - we should test it :)