[GO]Changes ByteArray mapping from String to []byte.

Created by: codedevstem

Potentially BREAKING Changes I think this makes Go more inline with other typed languages like Java. I am a bit unsure how breaking the changes are, would love some pointers here.

Changes

• Changes AbstractGoCodegen typemapping ByteArray value to []byte.

Validation

• Changes can be validated with model_fomat_test.go

Reviewers

@antihax (2017/11) @grokify (2018/07) @kemokemo (2018/09) @jirikuncar (2021/01)

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