Add handle for circular exceptions in SecretsMasker.

[Crowiant]

In the case of circular exceptions, Airflow 2 runs into a retry cycle without showing anything inside the task logs.

Here is the example that I used to reproduce the issue:

try:
    try:
        raise ValueError("Original crash simulation")
    except ValueError as err:
        # Create an intentional circular reference in the context
        err.__context__ = err
        raise RuntimeError("Wrapper error") from err
except Exception:
    # logger.exception triggers _redact_exception_with_context (no depth limit)
    logger.exception("This will trigger RecursionError in the SecretsMasker")

These changes will prevent this and show all exceptions to the user.

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[molcay]

LGTM

[potiuk]

I am closing it in favour of #61776. Since it is also present in main, I recreated it there, and will backport it to both v3-1-test and v2-11-test, I also added test coverage, but also updated that change (result of testing) - rather than stopping redacting when recursion level is reached, we will SKIP those exceptions and replace the remaining stack trace with sentinel exception explaining that this happened.

This is much safer, because potentially we could leak some secrets in those unredacted exceptions remaining on stack trace.

I made you co-author of #61776 @Crowiant

[potiuk]

Cherry-picked to 2-11-test in #61797