`StackdriverTaskHandler` rework for the structlog era

[amoghrajesh]

Body

Following #48491

Reference: #48788

In Airflow 3, the task execution path was rearchitected: task workers now use structlog and communicate with a RemoteLogIO (set as REMOTE_TASK_LOGin the logging config module) rather than through a Python stdlib logging. Handler registered inDEFAULT_LOGGING_CONFIG`.

All major remote log backends have been migrated to this new pattern — S3, GCS, CloudWatch, WASB, OSS, HDFS (recently in #48788), and Elasticsearch. Similar effort is needed for StackDriver

Committer

• I acknowledge that I am a maintainer/committer of the Apache Airflow project.