Fix Supervisor crash in Stackdriver remote log IO

[23tae]

This PR prevents the Airflow 3 Supervisor process from crashing entirely when transient network or IAM errors occur during Stackdriver log transmission.

Description

This PR addresses Bug 3 described in #68240.

In the new Airflow 3 Task SDK architecture, the StackdriverRemoteLogIO handler runs within the Supervisor process rather than the task process itself. If an exception is raised during _transport.send(), it propagates upwards and crashes the entire Supervisor process, disrupting task monitoring.

Key changes

• Exception Handling: Wrapped the _transport.send() call in a try...except Exception block. When a transmission fails, the exception is safely caught, and a warning is logged using the internal _logger. This ensures the Supervisor process remains highly resilient.

Verification Results

I have verified the changes using prek and breeze.

• Static Checks (Prek): Passed
• Unit Tests (Breeze): Passed

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related: #68240

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Was generative AI tooling used to co-author this PR?

• Yes

Generated-by: Antigravity following the guidelines

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