Use default_factory when dataclass defaults are hashable

[Cyclam]

Python 3.11 dataclasses require hashable defaults to use a default_factory.

This PR implements that for the az aosm extension.

Fixes #6426 (comment)

Testing that this resolves all instance of the mutable default is not allowed error to be completed by @yanzhudd, as agreed offline.

Function testing of the extension has been completed using the test suite with live tests.

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[yonzhan]

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[azclibot]

[Release] Update index.json for extension [ aosm ] : https://dev.azure.com/azclitools/internal/_build/results?buildId=99986&view=results