Don't treat not as an array (in contrast to allOf, anyOf, oneOf)

[shockey]

Description

This fixes Swagger-UI's incorrect parsing of Schema object not values. It looks like I introduced this problem - looking back at the RC1 definitions I wrote to implement against, the Schema Object definition had an invalid array under the not key (presumably a result of copy-pasting anyOf/oneOf). Mea culpa!

Per JSON Schema (emphasis mine):

allOf

The value of this keyword MUST be an array. This array MUST have at least one element.

Each element of this array MUST be an object, and each object MUST be a valid JSON Schema.

anyOf

The value of this keyword MUST be an array. This array MUST have at least one element.

Each element of this array MUST be an object, and each object MUST be a valid JSON Schema.

oneOf

The value of this keyword MUST be an array. This array MUST have at least one element.

Each element of this array MUST be an object, and each object MUST be a valid JSON Schema.

not

The value of this keyword MUST be an object. This object MUST be a valid JSON Schema.

Motivation and Context

Fixes #3932.

How Has This Been Tested?

• Manually tested (screenshot below).

Screenshots (if appropriate):

Types of changes

• No code changes (changes to documentation, CI, metadata, etc)
• Dependency changes (any modification to dependencies in package.json)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.