chore(airflow): bump Airflow example to 2.11.x, fix cached_property imports (#77)

Bumps airflow/requirements-dev.txt to the latest Airflow 2.x series:
- apache-airflow ~=2.2.2 -> ~=2.11.0
- apache-airflow-providers-amazon ~=4.0 -> ~=9.22
- pytest ~=7.1.2 -> ~=9.0

Also fixes long-standing import errors in the custom EMR Serverless
operator/hook: airflow.compat.functools was removed in Airflow 2.4, so
those imports are replaced with stdlib functools.cached_property. The
dead Python 3.7 fallback block in operators/emr.py is also removed
(Airflow 2.9+ requires Python 3.8+, 2.11 requires 3.9+).

Clears Dependabot alerts: #47 #48 #49 #52 #53 #55 #56 #57 #58 #59 #60
#61 #62 #63 #64 #65 #68 #75 #76 #77 #78 #79 #81 #86 (24 alerts total).
Alerts #87 #88 #89 require Airflow 3.2.0 which is incompatible with
custom operator APIs and out of scope here.

Verified:
- apache-airflow 2.11.0 + providers-amazon 9.26.0 + pytest 9.0.3 install
  cleanly under Python 3.11
- All custom hooks/operators/sensors import without error
- test_dag_integrity passes
- test_simple_submit has pre-existing issues using removed DAG.run() and
  schedule_interval APIs; those are integration tests against live EMR-S,
  out of scope for this PR

Author: knkarthik01

airflow/emr_serverless/hooks/emr.py

@@ -17,12 +17,12 @@
 # under the License.
 from __future__ import annotations
 
+from functools import cached_property
 from time import sleep
 from typing import Any, Callable
 
 from botocore.config import Config
 
-from airflow.compat.functools import cached_property
 from airflow.exceptions import AirflowException
 from airflow.providers.amazon.aws.hooks.base_aws import AwsBaseHook
 

airflow/emr_serverless/operators/emr.py

@@ -17,7 +17,7 @@
 # under the License.
 from __future__ import annotations
 
-import sys
+from functools import cached_property
 from typing import TYPE_CHECKING, Dict, Optional, Sequence
 from uuid import uuid4
 
@@ -29,15 +29,8 @@
 if TYPE_CHECKING:
     from airflow.utils.context import Context
 
-from airflow.compat.functools import cached_property
-
 DEFAULT_CONN_ID = "aws_default"
 
-if sys.version_info >= (3, 8):
-    from functools import cached_property
-else:
-    from cached_property import cached_property
-
 
 class EmrServerlessCreateApplicationOperator(BaseOperator):
     """

airflow/requirements-dev.txt

@@ -1,4 +1,4 @@
-apache-airflow~=2.2.2
-apache-airflow-providers-amazon~=4.0
-pytest~=7.1.2
-boto3>=1.23.9,~=1.23
+apache-airflow~=2.11.0
+apache-airflow-providers-amazon~=9.22
+pytest~=9.0
+boto3>=1.23.9,~=1.23