Limit flask-session to <0.6

[Taragolis]

New version of Flask-Session breaks our AirflowDatabaseSessionInterface by add new arguments into the constructor sid_length, sequence, schema and bind_key and make all arguments are mandatory include previously optional use_signer and permanent

Test OpenAPI client

Run airflow db init
/home/runner/actions-runner/_work/airflow/airflow/airflow/cli/commands/db_command.py:47 DeprecationWarning: `db init` is deprecated.  Use `db migrate` instead to migrate the db and/or airflow connections create-default-connections to create the default connections
DB: sqlite:////home/runner/airflow/airflow.db
[2024-01-19T09:50:[35](https://github.com/apache/airflow/actions/runs/7582079179/job/20650960654?pr=36893#step:12:36).350+0000] {migration.py:216} INFO - Context impl SQLiteImpl.
[2024-01-19T09:50:35.352+0000] {migration.py:219} INFO - Will assume non-transactional DDL.
Traceback (most recent call last):
  File "/home/runner/actions-runner/_work/_tool/Python/3.8.18/x64/bin/airflow", line 8, in <module>
    sys.exit(main())
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/__main__.py", line 57, in main
    args.func(args)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/cli/cli_config.py", line 49, in command
    return func(*args, **kwargs)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/providers_configuration_loader.py", line 55, in wrapped_function
    return func(*args, **kwargs)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/cli/commands/db_command.py", line 53, in initdb
    db.initdb()
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/session.py", line 79, in wrapper
    return func(*args, session=session, **kwargs)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/db.py", line 732, in initdb
    _create_db_from_orm(session=session)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/db.py", line 717, in _create_db_from_orm
    _create_flask_session_tbl(engine.url)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/db.py", line 710, in _create_flask_session_tbl
    db = _get_flask_db(sql_database_uri)
  File "/home/runner/actions-runner/_work/airflow/airflow/airflow/utils/db.py", line 699, in _get_flask_db
    AirflowDatabaseSessionInterface(app=flask_app, db=db, table="session", key_prefix="")
TypeError: __init__() missing 6 required positional arguments: 'sequence', 'schema', 'bind_key', 'use_signer', 'permanent', and 'sid_length'
Error: Process completed with exit code 1.

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[potiuk]

I think we should also make an issue to fix it for the (near) future. Created an issue for that #36897

[ldacey]

Ahh thanks for this - pinning flask-session fixed the issue for me as well when I upgraded to 2.8.1 earlier. Never upgrade on a weekend right before bed...