Change set_current_context location

[romsharon98]

closes: #24483

checked this changed works by this dag:

from airflow.operators.python import get_current_context, PythonOperator


def some_function_in_your_library():
    return 'rom'

def some_function_in_your_library2(name):
    print(name)


def config(task_id):
    context = get_current_context()
    _result = context['ti'].xcom_pull(task_ids=task_id)
    return _result

user_defined_macros = {"config": config}

from airflow.models.dag import DAG

with DAG(dag_id='my_dag', user_defined_macros=user_defined_macros) as dag:
    task1 = PythonOperator(python_callable=some_function_in_your_library, task_id='my_task')
    task2 = PythonOperator(python_callable=some_function_in_your_library2, task_id='my_task2', op_kwargs={"name": "{{config('my_task')}}"})
    task1 >> task2

task2 print rom

cc: @vanchaxy

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[josh-fell]

This changes looks OK to me, but FWIW I did test the example in the PR description on 2.9.0 and it works out of the box without this change. Maybe there is another example (or even a test case) that shows the value of this update?