Add support for tested task group @glazunov996

[pankajastro]

Resolves Nested Subgroups #119 issue

Original PR: #141

Co-authored-by: Kuris [email protected]

closes: #119

Example YML DAG

default:
  default_args:
    owner: default_owner
    retries: 1
    retry_delay_sec: 300
    start_date: 2024-01-01
  default_view: tree
  max_active_runs: 1
  schedule_interval: 0 1 * * *
example_task_group:
  description: "this dag uses task groups"
  task_groups:
    task_group_1:
      tooltip: "this is a task group"
      dependencies: [task_1]
    task_group_2:
      tooltip: "this is a task group"
      parent_group_name: task_group_1
  tasks:
    task_1:
      operator: airflow.operators.bash_operator.BashOperator
      bash_command: "echo 1"
    task_2:
      operator: airflow.operators.bash_operator.BashOperator
      bash_command: "echo 2"
      task_group_name: task_group_1
    task_4:
      operator: airflow.operators.bash_operator.BashOperator
      bash_command: "echo 4"
      task_group_name: task_group_2

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 84.21053% with 6 lines in your changes missing coverage. Please review.

Project coverage is 93.22%. Comparing base (841c5ff) to head (45b114b).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
dagfactory/dagbuilder.py	84.21%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #292      +/-   ##
==========================================
- Coverage   93.95%   93.22%   -0.74%     
==========================================
  Files           8        8              
  Lines         645      664      +19     
==========================================
+ Hits          606      619      +13     
- Misses         39       45       +6     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

---

🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests

[pankajkoti]

mostly looks good to me, have some comments inline

[pankajkoti]

LGTM. Thanks for addressing the previous comments so quickly!