Add some tasks using BashOperator in TaskGroup example dag (#11072)

Previously all the tasks in airflow/example_dags/example_task_group.py were using DummyOperator which does not go to executor and is marked as success in Scheduler itself so it would be good to have some tasks that aren't dummy operator to properly test TaskGroup functionality

GitOrigin-RevId: 45639cd99c2634fde8b53c74eb8bbda1db66005d

Author: kaxil

airflow/example_dags/example_task_group.py

@@ -19,6 +19,7 @@
 """Example DAG demonstrating the usage of the TaskGroup."""
 
 from airflow.models.dag import DAG
+from airflow.operators.bash import BashOperator
 from airflow.operators.dummy_operator import DummyOperator
 from airflow.utils.dates import days_ago
 from airflow.utils.task_group import TaskGroup
@@ -30,7 +31,7 @@
     # [START howto_task_group_section_1]
     with TaskGroup("section_1", tooltip="Tasks for section_1") as section_1:
         task_1 = DummyOperator(task_id="task_1")
-        task_2 = DummyOperator(task_id="task_2")
+        task_2 = BashOperator(task_id="task_2", bash_command='echo 1')
         task_3 = DummyOperator(task_id="task_3")
 
         task_1 >> [task_2, task_3]
@@ -42,7 +43,7 @@
 
         # [START howto_task_group_inner_section_2]
         with TaskGroup("inner_section_2", tooltip="Tasks for inner_section2") as inner_section_2:
-            task_2 = DummyOperator(task_id="task_2")
+            task_2 = BashOperator(task_id="task_2", bash_command='echo 1')
             task_3 = DummyOperator(task_id="task_3")
             task_4 = DummyOperator(task_id="task_4")