[GO] Fix for Pass by value/Pass by Reference changes which is breaking the go client

[the-akhil-nair]

The commit aeneasr@0c5e5ae in the PR : #8491 resolves the pointer issue, missed the logic to perform similar operation in case of Unmarshalling of the JSON.

Due to this, there is a mismatch between the data type(This issue is seen for array of object type property) between Dog type and DogWithoutEmbeddedStruct type(Present inside Unmarshalling method).

Applying the same logic mentioned in the above commit in UnmarshalJSON method.

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[wing328]

@the-akhil-nair thanks for the PR, which has been merged.