[ci] Deprecate flake8 (#8409)

* [ci] Deprecate flake8

* Addressing @villebro's comments

superset/models/core.py

@@ -16,21 +16,23 @@
 # under the License.
 # pylint: disable=C,R,W
 """A collection of ORM sqlalchemy models for Superset"""
-from contextlib import closing
-from copy import copy, deepcopy
-from datetime import datetime
 import json
 import logging
 import textwrap
+from contextlib import closing
+from copy import copy, deepcopy
+from datetime import datetime
 from typing import List
+from urllib import parse
 
+import numpy
+import pandas as pd
+import sqlalchemy as sqla
+import sqlparse
 from flask import escape, g, Markup, request
 from flask_appbuilder import Model
 from flask_appbuilder.models.decorators import renders
 from flask_appbuilder.security.sqla.models import User
-import numpy
-import pandas as pd
-import sqlalchemy as sqla
 from sqlalchemy import (
     Boolean,
     Column,
@@ -50,7 +52,6 @@ from sqlalchemy.orm.session import make_transient
 from sqlalchemy.pool import NullPool
 from sqlalchemy.schema import UniqueConstraint
 from sqlalchemy_utils import EncryptedType
-import sqlparse
 
 from superset import app, db, db_engine_specs, is_feature_enabled, security_manager
 from superset.connectors.connector_registry import ConnectorRegistry
@@ -60,7 +61,6 @@ from superset.models.tags import ChartUpdater, DashboardUpdater, FavStarUpdater
 from superset.models.user_attributes import UserAttribute
 from superset.utils import cache as cache_util, core as utils
 from superset.viz import viz_types
-from urllib import parse  # noqa
 
 config = app.config
 custom_password_store = config.get("SQLALCHEMY_CUSTOM_PASSWORD_STORE")
@@ -71,7 +71,7 @@ metadata = Model.metadata  # pylint: disable=no-member
 PASSWORD_MASK = "X" * 10
 
 
-def set_related_perm(mapper, connection, target):  # noqa
+def set_related_perm(mapper, connection, target):
     src_class = target.cls_model
     id_ = target.datasource_id
     if id_:
@@ -167,14 +167,14 @@ class Slice(Model, AuditMixinNullable, ImportMixin):
     perm = Column(String(1000))
     owners = relationship(security_manager.user_model, secondary=slice_user)
 
-    export_fields = (
+    export_fields = [
         "slice_name",
         "datasource_type",
         "datasource_name",
         "viz_type",
         "params",
         "cache_timeout",
-    )
+    ]
 
     def __repr__(self):
         return self.slice_name or str(self.id)
@@ -424,14 +424,14 @@ class Dashboard(Model, AuditMixinNullable, ImportMixin):
     owners = relationship(security_manager.user_model, secondary=dashboard_user)
     published = Column(Boolean, default=False)
 
-    export_fields = (
+    export_fields = [
         "dashboard_title",
         "position_json",
         "json_metadata",
         "description",
         "css",
         "slug",
-    )
+    ]
 
     def __repr__(self):
         return self.dashboard_title or str(self.id)
@@ -750,7 +750,7 @@ class Database(Model, AuditMixinNullable, ImportMixin):
     )
     perm = Column(String(1000))
     impersonate_user = Column(Boolean, default=False)
-    export_fields = (
+    export_fields = [
         "database_name",
         "sqlalchemy_uri",
         "cache_timeout",
@@ -759,7 +759,7 @@ class Database(Model, AuditMixinNullable, ImportMixin):
         "allow_ctas",
         "allow_csv_upload",
         "extra",
-    )
+    ]
     export_children = ["tables"]
 
     def __repr__(self):