class_id of token.EventIssue contains unnecessary characters

[brew0722]

Summary of Bug

when I executed the lbm tx token issue, it will be returned below.

                {
                    "type": "lbm.token.v1.EventIssue",
                    "attributes": [
                        {
                            "key": "class_id",
                            "value": "\"678c146a\""
                        }
                    ]

If you look at the value, it contains ", which seems unnecessary.

Version

e2acac9

Steps to Reproduce

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[0Tech]

Because TypedEvent may contain arbitrary structures, it uses json formated value. So you must unmarshal the value.

[zemyblue]

This is same issue with #463 .