Add Changelog for 2.2.2rc2

Author: kaxil

CHANGELOG.txt

@@ -1,4 +1,4 @@
-Airflow 2.2.2, 2021-11-12
+Airflow 2.2.2, 2021-11-15
 -------------------------
 
 Bug Fixes
@@ -24,6 +24,7 @@ Bug Fixes
 - Use ``execution_date`` to check for existing ``DagRun`` for ``TriggerDagRunOperator`` (#18968)
 - Add explicit session parameter in ``PoolSlotsAvailableDep`` (#18875)
 - FAB still requires ``WTForms<3.0`` (#19466)
+- Fix missing dagruns when ``catchup=True`` (#19528)
 
 Doc only changes
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