fix: preserve exception args when serializing built-in exceptions

[Vishwaspatel2401]

Description

BaseSerialization was adding an extra list/tuple layer around the args of built-in exceptions such as KeyError and AttributeError during serialization.

"args": [var.args]

Because var.args is already a tuple, an exception such as KeyError("boom") was serialized incorrectly:

from airflow.serialization.serialized_objects import BaseSerialization

result = BaseSerialization.deserialize(
    BaseSerialization.serialize(KeyError("boom"))
)

result.args  # (("boom",),) instead of ("boom",)

This change preserves the exception’s original args exactly during serialization and deserialization.

Closes #69743.

Tests

Added parametrized test cases to test_serialize_deserialize in test_serialized_objects.py covering:

• KeyError("boom")
• AttributeError("boom")
• KeyError("a", "b")

The tests verify that .args is preserved exactly after serialization and deserialization. All 40 parametrized test cases pass.

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