fix(superset.cli): superset cli group doesn't support superset extension app (#17539)

UPDATING.md

@@ -34,7 +34,9 @@ assists people when migrating to a new version.
 ### Potential Downtime
 
 - [16756](https://github.com/apache/incubator-superset/pull/16756): a change which renames the `dbs.allow_csv_upload` column to `dbs.allow_file_upload` via a (potentially locking) DDL operation.
-
+- [17539](https://github.com/apache/superset/pull/17539): all Superset CLI commands
+  (init, load_examples and etc) require setting the FLASK_APP environment variable
+  (which is set by default when .flaskenv is loaded)
 ### Deprecations
 
 ### Other

superset/cli.py

@@ -37,7 +37,6 @@ from flask_appbuilder import Model
 from flask_appbuilder.api import BaseApi
 
 from superset import app, appbuilder, config, security_manager
-from superset.app import create_app
 from superset.extensions import celery_app, db
 from superset.utils import core as utils
 from superset.utils.celery import session_scope
@@ -73,9 +72,7 @@ def normalize_token(token_name: str) -> str:
 
 
 @click.group(
-    cls=FlaskGroup,
-    create_app=create_app,
-    context_settings={"token_normalize_func": normalize_token},
+    cls=FlaskGroup, context_settings={"token_normalize_func": normalize_token},
 )
 @with_appcontext
 def superset() -> None: