Apache Airflow 2.2.4

## Bug Fixes - Adding missing login provider related methods from Flask-Appbuilder (#21294) - Fix slow DAG deletion due to missing ``dag_id`` index for job table (#20282) - Add a session backend to store session data in the database (#21478) - Show task status only for running dags or only for the last finished dag (#21352) - Use compat data interval shim in log handlers (#21289) - Fix mismatch in generated run_id and logical date of DAG run (#18707) - Fix TriggerDagRunOperator extra link (#19410) - Add possibility to create user in the Remote User mode (#19963) - Avoid deadlock when rescheduling task (#21362) - Fix the incorrect scheduling time for the first run of dag (#21011) - Fix Scheduler crash when executing task instances of missing DAG (#20349) - Deferred tasks does not cancel when DAG is marked fail (#20649) - Removed duplicated dag_run join in ``Dag.get_task_instances()`` (#20591) - Avoid unintentional data loss when deleting DAGs (#20758) - Fix session usage in ``/rendered-k8s`` view (#21006) - Fix ``airflow dags backfill --reset-dagruns`` errors when run twice (#21062) - Do not set ``TaskInstance.max_tries`` in ``refresh_from_task`` (#21018) - Don't require dag_id in body in dagrun REST API endpoint (#21024) - Add Roles from Azure OAUTH Response in internal Security Manager (#20707) - Allow Viewing DagRuns and TIs if a user has DAG "read" perms (#20663) - Fix running ``airflow dags test <dag_id> <execution_dt>`` results in error when run twice (#21031) - Switch to non-vendored latest connexion library (#20910) - Bump flask-appbuilder to ``>=3.3.4`` (#20628) - upgrade celery to ``5.2.3`` (#19703) - Bump croniter from ``<1.1`` to ``<1.2`` (#20489) - Lift off upper bound for MarkupSafe (#20113) - Avoid calling ``DAG.following_schedule()`` for ``TaskInstance.get_template_context()`` (#20486) - Fix(standalone): Remove hardcoded Webserver port (#20429) - Remove unnecssary logging in experimental API (#20356) - Un-ignore DeprecationWarning (#20322) - Deepcopying Kubernetes Secrets attributes causing issues (#20318) - Fix(dag-dependencies): fix arrow styling (#20303) - Adds retry on taskinstance retrieval lock (#20030) - Correctly send timing metrics when using dogstatsd (fix schedule_delay metric) (#19973) - Enhance ``multiple_outputs`` inference of dict typing (#19608) - Fixing ses email backend (#18042) - Pin Markupsafe until we are able to upgrade Flask/Jinja (#21664) ## Doc only changes - Added explaining concept of logical date in DAG run docs (#21433) - Add note about Variable precedence with env vars (#21568) - Update error docs to include before_send option (#21275) - Augment xcom docs (#20755) - Add documentation and release policy on "latest" constraints (#21093) - Add a link to the DAG model in the Python API reference (#21060) - Added an enum param example (#20841) - Compare taskgroup and subdag (#20700) - Add note about reserved ``params`` keyword (#20640) - Improve documentation on ``Params`` (#20567) - Fix typo in MySQL Database creation code (Set up DB docs) (#20102) - Add requirements.txt description (#20048) - Clean up ``default_args`` usage in docs (#19803) - Add docker-compose explanation to conn localhost (#19076) - Update CSV ingest code for tutorial (#18960) - Adds Pendulum 1.x -> 2.x upgrade documentation (#18955) - Updating explicit arg example in TaskFlow API tutorial doc (#18907) - Adds back documentation about context usage in Python/`@task` (#18868) - Clean up dynamic `start_date` values from docs (#19607) - Docs for multiple pool slots (#20257) - Update upgrading.rst with detailed code example of how to resolve post-upgrade warning (#19993) ## Misc - Deprecate some functions in the experimental API (#19931) - Deprecate smart sensors (#20151)