Fixed #400 - unset not working for systemuser

[sumanth-lingappa]

In NITRO documentation, the attributes type is str, int, list etc. But these attributes when present in "unset" operation, their type changes to bool.
Hence for all the attributes present in "unset" action, their type is changed to "raw" so that ansible should not throw error for type-mismatch

[github-actions]

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