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

Created by: the-akhil-nair

The commit https://github.com/aeneasr/openapi-generator/commit/0c5e5aeccc9fa2ef392c8fd0a3dd0b219665ec5d in the PR : https://github.com/OpenAPITools/openapi-generator/pull/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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