fix: conversion of JsonObject to Constraint

[ndr-brt]

What this PR changes/adds

Add missing unwrapping of JsonValue types also when the input is a JsonArray.

Why it does that

Avoid weird serialized types when Constraing.rightOperand is an array

Further notes

THIS IS A BREAKING CHANGE: until 0.18.0, when a rightOperand of a Constraint type in a PolicyDefinition contained a List, it would got stored into database as something like:

    "rightOperand": {
        "value":[{
            "@value":{"valueType":"STRING","chars":"item1","string":"item2"}
        },{
            "@value":{"valueType":"STRING","chars":"item2","string":"item2"}
        }]   
    }

this because the incoming JsonArray from the API's json-ld was not unwrapped and the type was stored as it was.
So, if in your control-plane do you have PolicyDefinitions with a multi-value rightOperand, you should migrate every one of those into:

    "rightOperand": {
        "value":["item1", "item2"]
    }

It could become tricky to write an automatic script to do that, so our advice would be to update the affected policies with an API call passing the same bodies that were used to create them.

Please also note that if you adapted your policy functions to workaround this bug, you'll need to update them as well.

Who will sponsor this feature?

Please @-mention the committer that will sponsor your feature.

Linked Issue(s)

Closes #5792
Related to #5934

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