refactor(NetworkPrefabHandler): reduce effort cognitive for understand this

[MarcusSilvaDev]

Some points fixed:

• Reduce nested if.
• Reduce complexity cyclomatic.
• add Guard clauses.

[unity-cla-assistant]

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:white_check_mark: MarcusViniciusSS
:x: Marcus.Silva

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[EmandM]

Closing this as the changes are out of date.