Prevent validation errors in Start Document JSON Schema

[DiamondJoseph]

Description

Changes validation properties that are enums to define the enums as an array

Motivation and Context

Current state is not valid Json Schema and causes exceptions when attempting to be ingested. Alternative valid solution: "enum": "value" -> "string" : "value" (knowing that the potential value of the string comes from an enumeration) makes validation logic clearer to parse, but fails JsonSchema3 tests

How Has This Been Tested?

Tested in an online JSON Schema linter, equivalent changes in use in AsyncAPI schema for BlueAPI (in progress)

[danielballan]

Thanks @DiamondJoseph, looks good.