Allow string conversion to datetime for since_time in KPO logs

[karenbraganz]

The since_seconds attribute in consume_logs (from class PodManager) and _write_logs (from class KubernetesPodOperator) is converted to None if since_time is not a datetime object. I have introduced code to check whether since_time is a string and convert it to a datetime object if possible instead of None.

This was suggested in PR #65232

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[Copilot]

Pull request overview

This PR extends KubernetesPodOperator/PodManager log fetching to handle since_time values provided as ISO-8601 strings by converting them into datetime objects instead of silently falling back to None.

Changes:

• Convert string since_time values to datetimes in PodManager.fetch_container_logs() and KubernetesPodOperator._write_logs().
• Expand unit test coverage for valid datetime, invalid input, and ISO-string since_time handling.
• Refactor the PodManager since-time test to use time_machine rather than patching pendulum.now.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

File	Description
providers/cncf/kubernetes/src/airflow/providers/cncf/kubernetes/utils/pod_manager.py	Adds parsing of string since_time and broadens exception handling.
providers/cncf/kubernetes/src/airflow/providers/cncf/kubernetes/operators/pod.py	Adds parsing of string since_time in _write_logs and catches ValueError.
providers/cncf/kubernetes/tests/unit/cncf/kubernetes/utils/test_pod_manager.py	Adds/updates tests for datetime, invalid, and string since_time scenarios.
providers/cncf/kubernetes/tests/unit/cncf/kubernetes/operators/test_pod.py	Adds a new _write_logs test for string since_time and adjusts invalid-case test wording.

[jscheffl]

Cool, thanks for the improvement and rework!