Check task attribute before use in sentry.add_tagging() (apache#37143)

* Check task attribute before use in add_tagging

* Refactor sentry and add tests

---------

Co-authored-by: Lipu Fei <lipu.fei@kpn.com>

airflow/sentry/__init__.py

@@ -0,0 +1,29 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+"""Sentry Integration."""
+
+from __future__ import annotations
+
+from airflow.configuration import conf
+from airflow.sentry.blank import BlankSentry
+
+Sentry: BlankSentry = BlankSentry()
+if conf.getboolean("sentry", "sentry_on", fallback=False):
+    from airflow.sentry.configured import ConfiguredSentry
+
+    Sentry = ConfiguredSentry()

airflow/sentry/blank.py

@@ -0,0 +1,40 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from sqlalchemy.orm import Session
+
+
+class BlankSentry:
+    """Blank class for Sentry."""
+
+    def add_tagging(self, task_instance):
+        """Blank function for tagging."""
+
+    def add_breadcrumbs(self, task_instance, session: Session | None = None):
+        """Blank function for breadcrumbs."""
+
+    def enrich_errors(self, run):
+        """Blank function for formatting a TaskInstance._run_raw_task."""
+        return run
+
+    def flush(self):
+        """Blank function for flushing errors."""