Add connexion<3.0 upper bound (#35218)

* Add connexion<3.0 upper bound

otherwise, breakage at import: airflow/www/extensions/init_views.py

Fix: /issues/35217

* Update setup.cfg

* Update setup.cfg

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Co-authored-by: Jarek Potiuk <jarek@potiuk.com>
(cherry picked from commit f592b2c)

setup.cfg

@@ -85,7 +85,13 @@ install_requires =
     # Update CustomTTYColoredFormatter to remove
     colorlog>=4.0.2, <5.0
     configupdater>=3.1.1
-    connexion[flask]>=2.10.0
+    # `airflow/www/extensions/init_views` imports `connexion.decorators.validation.RequestBodyValidator`
+    # connexion v3 has refactored the entire module to middleware, see: /spec-first/connexion/issues/1525
+    # Specifically, RequestBodyValidator was removed in: /spec-first/connexion/pull/1595
+    # The usage was added in #30596, seemingly only to override and improve the default error message.
+    # Either revert that change or find another way, preferably without using connexion internals.
+    # This limit can be removed after https://github.com/apache/airflow/issues/35234 is fixed
+    connexion[flask]>=2.10.0,<3.0
     cron-descriptor>=1.2.24
     croniter>=0.3.17
     cryptography>=0.9.3